Making Happy Users
It has been said, A day that is without troubles is not fulfilling. Rather, give
me a day of troubles well handled so that I can be content with my achievements.
In the world of computer networks, problems are as varied as the people who create them
or experience them. The design of the network implemented in the last chapter may
create problems for some network users. The following lists some of the problems that
may occur:
PDCnetwork bandwidthutilizationBDCuser accountPDC/BDC ratio
Notice: A significant number of network administrators have responded to the guidance given
below. It should be noted that there are sites that have a single PDC for many hundreds of
concurrent network clients. Network bandwidth, network bandwidth utilization, and server load
are among the factors that will determine the maximum number of Windows clients that
can be served by a single domain controller (PDC or BDC) on a network segment. It is possible
to operate with only a single PDC over a routed network. What is possible is not necessarily
best practice. When Windows client network logons begin to fail with
the message that the domain controller can not be found, or that the user account can not
be found (when you know it exists), that may be an indication that the DC is overloaded or
network bandwidth is overloaded. The guidance given in respect of PDC/BDC ratio to Windows
clients is conservative and if followed will minimize problems - but it is not absolute.
Users experiencing difficulty logging onto the networknetworklogonmultiple domain controllers
When a Windows client logs onto the network, many data packets are exchanged
between the client and the server that is providing the network logon services.
Each request between the client and the server must complete within a specific
time limit. This is one of the primary factors that govern the installation of
multiple domain controllers (usually called secondary or backup controllers).
As a rough rule, there should be one such backup controller for every
30 to 150 clients. The actual limits are determined by network operational
characteristics.
If the domain controller provides only network logon services
and all file and print activity is handled by Domain Member servers, one Domain
Controller per 150 clients on a single network segment may suffice. In any
case, it is highly recommended to have a minimum of one Domain Controller (PDC or BDC)
per network segment. It is better to have at least one BDC on the network
segment that has a PDC. If the Domain Controller is also used as a file and
print server, the number of clients it can service reliably is reduced
and a common rule is not to exceed 30 machines (Windows workstations plus
Domain Member servers) per Domain Controller.
Slow logons and log-offsslow logon
Slow logons and log-offs may be caused by many factors that include:
NetBIOSname resolutiondelaysWINSserver
Excessive delays in the resolution of a NetBIOS name to its IP
address. This may be observed when an overloaded domain controller
is also the WINS server. Another cause may be the failure to use
a WINS server (this assumes that there is a single network segment).
traffic collisionsHUBethernet switch
Network traffic collisions due to overloading of the network
segment &smbmdash; one short-term workaround to this may be to replace
network HUBs with ethernet switches.
networking hardwaredefective
Defective networking hardware. Over the past few years, we have seen
on the Samba mailing list a significant increase in the number of
problems that were traced to a defective network interface controller,
a defective HUB or Ethernet switch, or defective cabling. In most cases,
it was the erratic nature of the problem that ultimately pointed to
the cause of the problem.
profileroamingMS OutlookPST file
Excessively large roaming profiles. This type of problem is typically
the result of poor user eduction, as well as poor network management.
It can be avoided by users not storing huge quantities of email in
MS Outlook PST files, as well as by not storing files on the desktop.
These are old bad habits that require much discipline and vigilance
on the part of network management.
WebClient
You should verify that the Windows XP WebClient service is not running.
The use of the WebClient service has been implicated in many Windows
networking related problems.
Loss of access to network drives and printer resources
Loss of access to network resources during client operation may be caused by a number
of factors including:
networkoverload
Network overload (typically indicated by a high network collision rate)
Server overload
networktimeout
Timeout causing the client to close a connection that is in use, but has
been latent (no traffic) for some time (5 minutes or more)
network hardwaredefective
Defective networking hardware
datacorruption
No matter what the cause, a sudden loss of access to network resources can
result in BSOD (blue screen of death) situations that necessitate rebooting of the client
workstation. In the case of a mild problem, retrying to access the network drive of printer
may restore operations, but in any case this is a serious problem as it may lead to the next
problem, data corruption.
Potential data corruptiondatacorruption
Data corruption is one of the most serious problems. It leads to uncertainty, anger, and
frustration, and generally precipitates immediate corrective demands. Management response
to this type of problem may be rational, as well as highly irrational. There have been
cases where management has fired network staff for permitting this situation to occur without
immediate correction. There have been situations where perfectly functional hardware was thrown
out and replaced, only to find the problem caused by a low-cost network hardware item. There
have been cases where server operating systems were replaced, or where Samba was updated,
only to later isolate the problem due to defective client software.
In this chapter, you can work through a number of measures that significantly arm you to
anticipate and to combat network performance issues. You can work through complex and thorny
methods to improve the reliability of your network environment, but be warned that all such steps
demand the price of complexity.
Regarding LDAP Directories and Windows Computer AccountsLDAPdirectory
Computer (machine) accounts can be placed where ever you like in an LDAP directory subject to some
constraints that are described in this section.
POSIXSambaSAMAccountmachine accounttrust account
The POSIX and SambaSAMAccount components of computer (machine) accounts are both used by Samba.
i.e.: Machine accounts are treated inside Samba in the same way that Windows NT4/200X treats
them. A user account and a machine account are indistinguishable from each other, except that
the machine account ends in a '$' character, as do trust accounts.
accountUID
The need for Windows user, group, machine, trust, etc. accounts to be tied to a valid UNIX UID
is a design decision that was made a long way back in the history of Samba development. It is
unlikely that this decision will be reversed of changed during the remaining life of the
Samba-3.x series.
SIDNSS
The resolution of a UID from the Windows SID is achieved within Samba through a mechanism that
must refer back to the host operating system on which Samba is running. The name service
switch (NSS) is the preferred mechanism that shields applications (like Samba) from the
need to know everything about every host OS it runs on.
Samba asks the host OS to provide a UID via the passwd, shadow
and group facilities in the NSS control (configuration) file. The best tool
for achieving this is left up to the UNIX administrator to determine. It is not imposed by
Samba. Samba provides winbindd together with its support libraries as one method. It is
possible to do this via LDAP - and for that Samba provides the appropriate hooks so that
all account entities can be located in an LDAP directory.
nss_ldap
For many the weapon of choice is to use the PADL nss_ldap utility. This utility must
be configured so that computer accounts can be resolved to a POSIX/UNIX account UID. That
is fundamentally an LDAP design question. The information provided on the Samba list and
in the documentation is directed at providing working examples only. The design
of an LDAP directory is a complex subject that is beyond the scope of this documentation.
Introduction
Mr. Bob Jordan just opened an email from Christine that reads:
Bob,
Christine
A few months ago we sat down to design the network. We discussed the challenges ahead and we all
agreed to compromise our design to keep it simple. We knew there would be problems, but anticipated
that we would have some time to resolve any issues that might be encountered.
As you now know we started off on the wrong foot. We have a lot of unhappy users. One of them
resigned yesterday afternoon because she was under duress to complete some critical projects. She
suffered a blue screen of death situation just as she was finishing four hours of intensive work, all
of which was lost. She has a unique requirement that involves storing large files on her desktop.
Mary's desktop profile is nearly 1 Gigabyte in size. As a result of her desktop configuration, it
takes her nearly 15 minutes just to log onto her workstation. But that is not enough. Because all
network logon traffic passes over the network links between our buildings, logging on may take
three or four attempts due to blue screen problems associated with network timeouts.
A few of us worked to help her out of trouble. We convinced her to stay and promised to fully
resolve the difficulties she is facing. We have no choice. We must implement LDAP and set hard
limits on what our users can do with their desktops. If we do not do this, we face staff losses
that can surely do harm to our growth, as well as to staff morale. I am sure we can better deal
with the consequences of what we know we must do than we can with the unrest we have now.
Stan and I have discussed the current situation. We are resolved to help our users and protect
the well being of Abmas. Please acknowledge this advice with consent to proceed as required to
regain control of our vital IT operations.
compromisenetworkmulti-segment
Every compromise has consequences. Having a large routed (i.e., multi-segment) network with only a
single domain controller is a poor design that has obvious operational effects that may
frustrate users. Here is Bob's reply:
Bob
Christine, Your diligence and attention to detail are much valued. Stan and I fully support your
proposals to resolve the issues. I am confident that your plans fully realized will significantly
boost staff morale. Please go ahead with your plans. If you have any problems, please let me know.
Please let Stan know what the estimated cost will be so I can approve the expense. Do not wait
for approval; I appreciate the urgency.
Assignment Tasks
The priority of assigned tasks in this chapter is:
Backup Domain ControllerBDCBDCtdbsamLDAPmigration
Implement Backup Domain Controllers (BDCs) in each building. This involves
a change from use of a tdbsam backend that was used in the previous
chapter, to use an LDAP-based backend.
You can implement a single central LDAP server for this purpose.
logon timenetwork sharedefault profileprofiledefault
Rectify the problem of excessive logon times. This involves redirection of
folders to network shares as well as modification of all user desktops to
exclude the redirected folders from being loaded at login time. You can also
create a new default profile that can be used for all new users.
disk image
You configure a new MS Windows XP Professional Workstation disk image that you
roll out to all desktop users. The instructions you have created are followed on a
staging machine from which all changes can be carefully tested before inflicting them on
your network users.
CUPS
This is the last network example in which specific mention of printing is made. The example
again makes use of the CUPS printing system.
Dissection and DiscussionBDCLDAPOpenLDAP
The implementation of Samba BDCs necessitates the installation and configuration of LDAP.
For this site, you use OpenLDAP, the open source software LDAP server platform. Commercial
LDAP servers in current use with Samba-3 include:
eDirectoryNovell eDirectory.
eDirectory is being successfully used by some sites. Information on how to use eDirectory can be
obtained from the Samba mailing lists or from Novell.
Tivoli Directory Server
IBM Tivoli Directory Server,
can be used to provide the Samba LDAP backend. Example schema files are provided in the Samba
source code tarball under the directory ~samba/example/LDAP.Sun ONE Identity Server
Sun ONE Identity Server.
This product suite provides an LDAP server that can be used for Samba. Example schema files are
provided in the Samba source code tarball under the directory ~samba/example/LDAP.
A word of caution is fully in order. OpenLDAP is purely an LDAP server and unlike commercial
offerings, it requires that you manually edit the server configuration files and manually
initialize the LDAP directory database. OpenLDAP itself has only command line tools to
help you to get OpenLDAP and Samba-3 running as required, albeit with some learning curve challenges.
Active Directory
For most sites, the deployment of Microsoft Active Directory from the shrink-wrapped installation is quite
adequate. If you are migrating from Microsoft Active Directory, be
warned that OpenLDAP does not include
GUI-based directory management tools. Even a simple task such as adding users to the OpenLDAP database
requires an understanding of what you are doing, why you are doing it, and the tools that you must use.
Identity Managementhigh availabilitydirectoryreplicationdirectorysynchronizationperformancedirectorymanagementdirectoryschema
When installed and configured, an OpenLDAP Identity Management backend for Samba functions well.
High availability operation may be obtained through directory replication/synchronization and
master/slave server configurations. OpenLDAP is a mature platform to host the organizational
directory infrastructure that can include all UNIX accounts, directories for electronic mail, and much more.
The price paid through learning how to design an LDAP directory schema in implementation and configuration
of management tools is well rewarded by performance and flexibility, and the freedom to manage directory
contents with greater ability to back up, restore, and modify the directory than is generally possible
with Microsoft Active Directory.
comparisonActive Directory & OpenLDAPADAMActive DirectoryOpenLDAP
A comparison of OpenLDAP with Microsoft Active Directory does not do justice to either. OpenLDAP is an LDAP directory
tool-set. Microsoft Active Directory Server is an implementation of an LDAP server that is largely pre-configured
for a specific task orientation. It comes with a set of administrative tools that is entirely customized
for the purpose of running MS Windows applications that include file and print services, Microsoft Exchange
server, Microsoft SQL server, and more. The complexity of OpenLDAP is highly valued by the UNIX administrator
who wants to built a custom directory solution. Microsoft provides an application called
MS ADAM that provides more-generic LDAP services, yet it does not have the vanilla-like services
of OpenLDAP.
directoryschemapassdb backend
You may wish to consider out-sourcing the development of your OpenLDAP directory to an expert, particularly
if you find the challenge of learning about LDAP directories, schemas, configuration, and management
tools, and the creation of shell and Perl scripts a bit
challenging. OpenLDAP can be easily customized, though it includes
many ready-to-use schemas. Samba-3 provides an OpenLDAP schema file
that is required for use as a passdb backend.
interoperability
For those who are willing to brave the process of installing and configuring LDAP and Samba-3 interoperability,
there are a few nice Web-based tools that may help you to manage your users and groups more effectively.
The Web-based tools you might like to consider include: The
LDAP Account Manager (LAM), as well as the
Webmin-based Idealx
CGI tools.
Some additional LDAP tools should be mentioned. Every so often a Samba user reports using one of
these so it may be useful to include passing reference to them.
The first is GQ, a GTK-based LDAP browser;
LDAP Browser/Editor,JXplorer (by Computer Associates),
and the last is called phpLDAPadmin.
The following prescriptive guidance is not an LDAP tutorial. The LDAP implementation expressly uses minimal
security controls. No form of secure LDAP communications is attempted. The LDAP configuration information provided
is considered to consist of the barest essentials only. You are strongly encouraged to learn more about
LDAP before attempting to deploy it in a business-critical environment.
Information to help you get started with OpenLDAP is available from the
OpenLDAP Web Site. Many people have found the book
LDAP System Administration,
written by Jerry Carter, quite useful.
BDCnetworksegmentperformancenetworkwide-area
Mary's problems are due to two factors. First, the absence of a domain controller on the local network is the
main cause of the errors that result in blue screen crashes. Second, Mary has a large profile that must
be loaded over the wide-area network connection. This addition of BDCs on each network segment significantly
improves overall network performance for most users, but this is not enough. You must gain control over
user desktops, and this must be done in a way that wins their support and does not cause further loss of
staff morale. The following procedures solve this problem.
smart printing
There is also an opportunity to implement smart printing features. You add this to the Samba configuration
so that future printer changes can be managed without need to change desktop configurations.
You add the ability to automatically download new printer drivers, even if they are not installed
in the default desktop profile. Only one example of printing configuration is given. It is assumed that
you can extrapolate the principles and use this to install all printers that may be needed.
Technical IssuesidentitymanagementdirectoryserverPosix
The solution provided is a minimal approach to getting OpenLDAP running as an identity management directory
server for UNIX system accounts as well as for Samba. From the OpenLDAP perspective, UNIX system
accounts are stored Posix schema extensions. Samba provides its own schema to permit storage of account
attributes Samba needs. Samba-3 can use the LDAP backend to store:
Windows Networking User AccountsWindows NT Group AccountsMapping Information between UNIX Groups and Windows NT GroupsID Mappings for SIDs to UIDs (also for foreign Domain SIDs)UNIX accountsWindows accountsPADL LDAP tools/etc/groupLDAPname service switchNSSNSSUIDnss_ldap
The use of LDAP with Samba-3 makes it necessary to store UNIX accounts as well as Windows Networking
accounts in the LDAP backend. This implies the need to use the
PADL LDAP tools. The resolution
of the UNIX group name to its GID must be enabled from either the /etc/group
or from the LDAP backend. This requires the use of the PADL nss_ldap tool-set
that integrates with the name service switch (NSS). The same requirements exist for resolution
of the UNIX username to the UID. The relationships are demonstrated in .
The Interaction of LDAP, UNIX Posix Accounts and Samba AccountsUNIX-Samba-and-LDAPsecurityLDAPsecure
You configure OpenLDAP so that it is operational. Before deploying the OpenLDAP, you really
ought to learn how to configure secure communications over LDAP so that site security is not
at risk. This is not covered in the following guidance.
PDCLDAP Interchange FormatLDIFLDIFsecrets.tdb
When OpenLDAP has been made operative, you configure the Primary Domain Controller (PDC)
called MASSIVE. You initialize the Samba secrets.tdb
file. Then you create the LDAP Interchange Format (LDIF) file from which the LDAP database
can be initialized. You need to decide how best to create user and group accounts. A few
hints are, of course, provided. You can also find on the enclosed CD-ROM, in the Chap06
directory, a few tools that help to manage user and group configuration.
folder redirectiondefault profileroaming profile
In order to effect folder redirection and to add robustness to the implementation,
create a network Default Profile. All network users workstations are configured to use
the new profile. Roaming profiles will automatically be deleted from the workstation
when the user logs off.
mandatory profile
The profile is configured so that users cannot change the appearance
of their desktop. This is known as a mandatory profile. You make certain that users
are able to use their computers efficiently.
logon script
A network logon script is used to deliver flexible but consistent network drive
connections.
Addition of Machines to the Domain
Samba versions prior to 3.0.11 necessitated the use of a domain administrator account
that maps to the UNIX UID=0. The UNIX operating system permits only the root
user to add user and group accounts. Samba 3.0.11 introduced a new facility known as
Privileges. This new facility introduced four new privileges that
can be assigned to users and/or groups:
Current Privilege CapabilitiesPrivilegeDescriptionSeMachineAccountPrivilegeAdd machines to domainSePrintOperatorPrivilegeManage printersSeAddUsersPrivilegeAdd users and groups to the domainSeRemoteShutdownPrivilegeForce shutdown from a remote systemSeDiskOperatorPrivilegeManage disk share
In this network example use will be made of one of the supported privileges purely to demonstrate
how any user can now be given the ability to add machines to the domain using a normal user account
that has been given the appropriate privileges.
Roaming Profile Background
As XP roaming profiles grow, so does the amount of time it takes to log in and out.
roaming profileHKEY_CURRENT_USERNTUSER.DAT%USERNAME%
An XP Roaming Profile consists of the HKEY_CURRENT_USER hive file
NTUSER.DAT and a number of folders (My Documents, Application Data,
Desktop, Start Menu, Templates, NetHood, Favorites, and so on). When a user logs onto the
network with the default configuration of MS Windows NT/200x/XPP, all this data is
copied to the local machine under the C:\Documents and Settings\%USERNAME%
directory. While the user is logged in, any changes made to any of these folders or to the
HKEY_CURRENT_USER branch of the registry are made to the local copy
of the profile. At logout the profile data is copied back to the server. This behavior
can be changed through appropriate registry changes and/or through changes to the Default
User profile. In the latter case, it updates the registry with the values that are set in the
profile NTUSER.DAT
file.
The first challenge is to reduce the amount of data that must be transferred to and
from the profile server as roaming profiles are processed. This includes removing
all the shortcuts in the Recent directory, making sure the cache used by the web browser
is not being dumped into the Application Data folder, removing the
Java plug-ins cache (the .jpi_cache directory in the profile), as well as training the
user to not place large files on the Desktop and to use his mapped home directory for
saving documents instead of the My Documents folder.
My Documents
Using a folder other than My Documents is a nuisance for
some users since many applications use it by default.
roaming profilesLocal Group PolicyNTUSER.DAT
The secret to rapid loading of roaming profiles is to prevent unnecessary data from
being copied back and forth, without losing any functionality. This is not difficult;
it can be done by making changes to the Local Group Policy on each client as well
as changing some paths in each user's NTUSER.DAT hive.
Network Default Profileredirected folders
Every user profile has their own NTUSER.DAT file. This means
you need to edit every user's profile, unless a better method can be
followed. Fortunately, with the right preparations, this is not difficult.
It is possible to remove the NTUSER.DAT file from each
user's profile. Then just create a Network Default Profile. Of course, it is
necessary to copy all files from redirected folders to the network share to which
they are redirected.
The Local Group PolicyGroup Policy ObjectsActive DirectoryPDCGroup Policy editor
Without an Active Directory PDC, you cannot take full advantage of Group Policy
Objects. However, you can still make changes to the Local Group Policy by using
the Group Policy editor (gpedit.msc).
The Exclude directories in roaming profile settings can
be found under
User ConfigurationAdministrative TemplatesSystemUser Profiles.
By default this setting contains:
Local Settings;Temporary Internet Files;History;Temp.
Simply add the folders you do not wish to be copied back and forth to this
semicolon-separated list. Note that this change must be made on all clients
that are using roaming profiles.
Profile ChangesNTUSER.DAT%USERNAME%
There are two changes that should be done to each user's profile. Move each of
the directories that you have excluded from being copied back and forth out of
the usual profile path. Modify each user's NTUSER.DAT file
to point to the new paths that are shared over the network, instead of the default
path (C:\Documents and Settings\%USERNAME%).
Default Userregedt32
The above modifies existing user profiles. So that newly created profiles have
these settings, you will need to modify the NTUSER.DAT in
the C:\Documents and Settings\Default User folder on each
client machine, changing the same registry keys. You could do this by copying
NTUSER.DAT to a Linux box and using regedt32.
The basic method is described under .
Using a Network Default User ProfileNETLOGONNTUSER.DAT
If you are using Samba as your PDC, you should create a file-share called
NETLOGON and within that create a directory called
Default User, which is a copy of the desired default user
configuration (including a copy of NTUSER.DAT).
If this share exists and the Default User folder exists,
the first login from a new account pulls its configuration from it.
See also:
the Real Men Don't Click Web site.
Installation of Printer Driver Auto-Downloadprintingdumbdumb printingRaw Print Through
The subject of printing is quite topical. Printing problems run second place to name
resolution issues today. So far in this book, you have experienced only what is generally
known as dumb printing. Dumb printing is the arrangement where all drivers
are manually installed on each client and the printing subsystems perform no filtering
or intelligent processing. Dumb printing is easily understood. It usually works without
many problems, but it has its limitations also. Dumb printing is better known as
Raw Print Through printing.
printingdrag-and-dropprintingpoint-n-click
Samba permits the configuration of Smart printing using the Microsoft
Windows point-and-click (also called drag-and-drop) printing. What this provides is
essentially the ability to print to any printer. If the local client does not yet have a
driver installed, the driver is automatically downloaded from the Samba server and
installed on the client. Drag-and-drop printing is neat; it means the user never needs
to fuss with driver installation, and that is a Good Thing,
isn't it?
There is a further layer of print job processing that is known as Intelligent
printing that automatically senses the file format of data submitted for printing and
then invokes a suitable print filter to convert the incoming data stream into a format
suited to the printer to which the job is dispatched.
CUPSEasy Software ProductsPostscript
The CUPS printing subsystem is capable of intelligent printing. It has the capacity to
detect the data format and apply a print filter. This means that it is feasible to install
on all Windows clients a single printer driver for use with all printers that are routed
through CUPS. The most sensible driver to use is one for a Postscript printer. Fortunately,
Easy Software Products, the authors of CUPS have
released a Postscript printing driver for Windows. It can be installed into the Samba
printing backend so that it automatically downloads to the client when needed.
This means that so long as there is a CUPS driver for the printer, all printing from Windows
software can use Postscript, no matter what the actual printer language for the physical
device is. It also means that the administrator can swap out a printer with a totally
different type of device without ever needing to change a client workstation driver.
This book is about Samba-3, so you can confine the printing style to just the smart
style of installation. Those interested in further information regarding intelligent
printing should review documentation on the Easy Software Products Web site.
Avoiding Failures &smbmdash; Solving Problems Before they Happen
It has often been said that there are three types of people in the world: Those who
have sharp minds and those that forget things. Please do not ask what the third group
are like! Well, it seems that many of us have company in the second group. There must
be a good explanation why so many network administrators fail to solve apparently
simple problems efficiently and effectively.
Here are some diagnostic guidelines that can be referred to when things go wrong:
Preliminary Advice &smbmdash; Dangers Can be Avoided
The best advice regarding how best to mend a broken leg was never break a leg!LDAP
New comers to Samba and LDAP seem to struggle a great deal at first. If you want advice
regarding the best way to remedy LDAP and Samba problems: Avoid them like the plague!
If you are now asking yourself how can problems be avoided? The best advice is to start
out your learning experience with a known-good configuration. After
you have seen a fully working solution, a good way to learn is to make slow and progressive
changes that cause things to break, then observe carefully how and why things ceased to work.
The examples in this chapter (also in the book as a whole) are known to work. That means
that they could serve as the kick-off point for your journey through fields of knowledge.
Use this resource carefully; we hope it serves you well.
Do not be lulled into thinking that you can easily adopt the examples in this
book and adapt them without first working through the working examples provided. A little
thing over-looked can cause untold pain and may permanently tarnish your experience.
The Name Service Caching Daemon (nscd)
The name service caching daemon (nscd) is a primary cause of difficulties with name
resolution, particularly where winbind is used. Winbind does its
own caching, thus nscd causes double caching which can lead to peculiar problems during
debugging. As a rule it is a good idea to turn off the name service caching daemon.
Operation of the name service caching daemon is controlled by the
/etc/nscd.conf file. Typical contents of this file are as follows:
# /etc/nscd.conf
# An example Name Service Cache config file. This file is needed by nscd.
# Legal entries are:
# logfile <file>
# debug-level <level>
# threads <threads to use>
# server-user <user to run server as instead of root>
# server-user is ignored if nscd is started with -S parameters
# stat-user <user who is allowed to request statistics>
# reload-count unlimited|<number>
#
# enable-cache <service> <yes|no>
# positive-time-to-live <service> <time in seconds>
# negative-time-to-live <service> <time in seconds>
# suggested-size <service> <prime number>
# check-files <service> <yes|no>
# persistent <service> <yes|no>
# shared <service> <yes|no>
# Currently supported cache names (services): passwd, group, hosts
# logfile /var/log/nscd.log
# threads 6
# server-user nobody
# stat-user somebody
debug-level 0
# reload-count 5
enable-cache passwd yes
positive-time-to-live passwd 600
negative-time-to-live passwd 20
suggested-size passwd 211
check-files passwd yes
persistent passwd yes
shared passwd yes
enable-cache group yes
positive-time-to-live group 3600
negative-time-to-live group 60
suggested-size group 211
check-files group yes
persistent group yes
shared group yes
# !!!!!WARNING!!!!! Host cache is insecure!!! The mechanism in nscd to
# cache hosts will cause your local system to not be able to trust
# forward/reverse lookup checks. DO NOT USE THIS if your system relies on
# this sort of security mechanism. Use a caching DNS server instead.
enable-cache hosts no
positive-time-to-live hosts 3600
negative-time-to-live hosts 20
suggested-size hosts 211
check-files hosts yes
persistent hosts yes
shared hosts yes
It is feasible to comment out the passwd and group
entries so they will not be cached. Alternately, it is often simpler to just disable the
nscd service by executing (on Novell SUSE Linux):
&rootprompt; chkconfig nscd off
&rootprompt; rcnscd off
Debugging LDAP/etc/openldap/slapd.confloglevelslapd
In the example /etc/openldap/slapd.conf control file
(see ) there is an entry for loglevel 256.
To enable logging via the syslog infrastructure it is necessary to uncomment this parameter
and restart slapd.
/etc/syslog.conf/var/log/ldaplogs
LDAP log information can be directed into a file that is separate from the normal system
log files by changing the /etc/syslog.conf file so it has the following
contents:
# Some foreign boot scripts require local7
#
local0,local1.* -/var/log/localmessages
local2,local3.* -/var/log/localmessages
local5.* -/var/log/localmessages
local6,local7.* -/var/log/localmessages
local4.* -/var/log/ldaplogs
In the above case, all LDAP related logs will be directed to the file
/var/log/ldaplogs. This makes it easy to track LDAP errors.
The above provides a simple example of usage that can be modified to suit
local site needs. The configuration used later in this chapter reflects such
customization with the intent that LDAP log files will be stored at a location
that meets local site needs and wishes more fully.
Debugging NSS_LDAP
The basic mechanism for diagnosing problems with the nss_ldap utility involves adding to the
/etc/ldap.conf file the following parameters:
debug 256
logdir /data/logs
Create the log directory as follows:
&rootprompt; mkdir /data/logs
The diagnostic process should follow the following steps:
Diagnostic Guidelines
Verify the nss_base_passwd, nss_base_shadow, nss_base_group entries
in the /etc/ldap.conf file and compare them closely with the directory
tree location that was chosen in when the directory was first created.
One way this can be done is by executing:
&rootprompt; slapcat | grep Group | grep dn
dn: ou=Groups,dc=abmas,dc=biz
dn: cn=Domain Admins,ou=Groups,dc=abmas,dc=biz
dn: cn=Domain Users,ou=Groups,dc=abmas,dc=biz
dn: cn=Domain Guests,ou=Groups,dc=abmas,dc=biz
dn: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
dn: cn=Administrators,ou=Groups,dc=abmas,dc=biz
dn: cn=Print Operators,ou=Groups,dc=abmas,dc=biz
dn: cn=Backup Operators,ou=Groups,dc=abmas,dc=biz
dn: cn=Replicators,ou=Groups,dc=abmas,dc=biz
The first line is the DIT entry point for the container for POSIX groups. The correct entry
for the /etc/ldap.conf for the nss_base_group
parameter therefore is the distinguished name (dn) as applied here:
nss_base_group ou=Groups,dc=abmas,dc=biz?one
The same process may be followed to determine the appropriate dn for user accounts.
If the container for computer accounts is not the same as that for users (see the &smb.conf;
file entry for ldap machine suffix, it may be necessary to set the
following DIT dn in the /etc/ldap.conf file:
nss_base_passwd dc=abmas,dc=biz?sub
This instructs LDAP to search for machine as well as user entries from the top of the DIT
down. This is inefficient, but at least should work. Note: It is possible to specify multiple
nss_base_passwd entries in the /etc/ldap.conf file, they
will be evaluated sequentially. Let us consider an example of use where the following DIT
has been implemented:
All user accounts are stored under the DIT: ou=Users,dc=abmas,dc=bizAll user login accounts are under the DIT: ou=People,ou-Users,dc=abmas,dc=bizAll computer accounts are under the DIT: ou=Computers,ou=Users,dc=abmas,dc=biz
The appropriate multiple entry for the nss_base_passwd directive
in the /etc/ldap.conf file may be:
nss_base_passwd ou=People,ou=Users,dc=abmas,dc=org?one
nss_base_passwd ou=Computers,ou=Users,dc=abmas,dc=org?one
Perform lookups such as:
&rootprompt; getent passwd
Each such lookup will create an entry in the /data/log directory
for each such process executed. The contents of each file created in this directory
may provide a hint as to the cause of the a problem that is under investigation.
For additional diagnostic information check the contents of the /var/log/messages
to see what error messages are being generated as a result of the LDAP lookups. Here is an example of
a successful lookup:
slapd[12164]: conn=0 fd=10 ACCEPT from IP=127.0.0.1:33539
(IP=0.0.0.0:389)
slapd[12164]: conn=0 op=0 BIND dn="" method=128
slapd[12164]: conn=0 op=0 RESULT tag=97 err=0 text=
slapd[12164]: conn=0 op=1 SRCH base="" scope=0 deref=0
filter="(objectClass=*)"
slapd[12164]: conn=0 op=1 SEARCH RESULT tag=101 err=0
nentries=1 text=
slapd[12164]: conn=0 op=2 UNBIND
slapd[12164]: conn=0 fd=10 closed
slapd[12164]: conn=1 fd=10 ACCEPT from
IP=127.0.0.1:33540 (IP=0.0.0.0:389)
slapd[12164]: conn=1 op=0 BIND
dn="cn=Manager,dc=abmas,dc=biz" method=128
slapd[12164]: conn=1 op=0 BIND
dn="cn=Manager,dc=abmas,dc=biz" mech=SIMPLE ssf=0
slapd[12164]: conn=1 op=0 RESULT tag=97 err=0 text=
slapd[12164]: conn=1 op=1 SRCH
base="ou=People,dc=abmas,dc=biz" scope=1 deref=0
filter="(objectClass=posixAccount)"
slapd[12164]: conn=1 op=1 SRCH attr=uid userPassword
uidNumber gidNumber cn
homeDirectory loginShell gecos description objectClass
slapd[12164]: conn=1 op=1 SEARCH RESULT tag=101 err=0
nentries=2 text=
slapd[12164]: conn=1 fd=10 closed
Check that the bindpw entry in the /etc/ldap.conf or in the
/etc/ldap.secrets file is correct. i.e.: As specified in the
/etc/openldap/slapd.conf file.
Debugging Samba
The following parameters in the &smb.conf; file can be useful in tracking down Samba related problems:
[global]
...
log level = 5
log file = /var/log/samba/%m.log
max log size = 0
...
This will result in the creation of a separate log file for every client from which connections
are made. The log file will be quite verbose and will grow continually. Do not forget to
change these lines to the following when debugging has been completed:
[global]
...
log level = 1
log file = /var/log/samba/%m.log
max log size = 50
...
The log file can be analyzed by executing:
&rootprompt; cd /var/log/samba
&rootprompt; grep -v "^\[200" machine_name.log
Search for hints of what may have failed by looking for the words fail
and error.
Debugging on the Windows Client
MS Windows 2000 Professional and Windows XP Professional clients are capable of being configured
to create a netlogon.log file that can be very helpful in diagnosing network logon problems. Search
the Microsoft knowledge base for detailed instructions. The techniques vary a little with each
version of MS Windows.
Political Issues
MS Windows network users are generally very sensitive to limits that may be imposed when
confronted with locked-down workstation configurations. The challenge you face must
be promoted as a choice between reliable and fast network operation, and a constant flux
of problems that result in user irritation.
Installation Check-List
You are starting a complex project. Even though you have gone through the installation
of a complex network in chapter 5, this network is a bigger challenge because of the
large number of complex applications that must be configured before the first few steps
can be validated. Take stock of what you are about to undertake, prepare yourself, and
frequently review the steps ahead while making at least a mental note of what has already
been completed. The following task list may help you to keep track of the task items
that are covered:
Samba-3 PDC Server ConfigurationDHCP and DNS ServersOpenLDAP ServerPAM and NSS Client ToolsSamba-3 PDCIdealx SMB-LDAP ScriptsLDAP InitializationCreate User and Group AccountsPrintersShare Point Directory RootsProfile DirectoriesLogon ScriptsConfiguration of User Rights and PrivilegesSamba-3 BDC Server ConfigurationDHCP and DNS ServersPAM and NSS Client ToolsPrintersShare Point Directory RootsProfiles DirectoriesWindows XP Client ConfigurationDefault Profile Folder RedirectionMS Outlook PST File RelocationDelete Roaming Profile on LogoutUpload Printer Drivers to Samba ServersInstall SoftwareCreation of Roll-out ImagesSamba Server Implementationfile serversBDC
The network design shown in is not comprehensive. It is assumed
that you will install additional file servers, and possibly additional BDCs.
Network Topology &smbmdash; 500 User Network Using ldapsam passdb backend.chap6-netSUSE LinuxRed Hat Linux
All configuration files and locations are shown for SUSE Linux 9.2 and are equally valid for SUSE
Linux Enterprise Server 9. The file locations for Red Hat Linux are similar. You may need to
adjust the locations for your particular Linux system distribution/implementation.
The following information applies to Samba-3.0.15 when used with the Idealx smbldap-tools scripts
version 0.8.8. If using a different version of Samba, or of the smbldap-tools tarball, please
verify that the versions you are about to use are matching. The smbldap-tools package uses counter
entries in the LDAP directory to avoid duplication of the UIDs and GIDs that are issued for POSIX
accounts. The LDAP rdn under which this information is stored are called uidNumber
and gidNumber respectively. These may be located in any convenient part of the
directory information tree (DIT). In the examples that follow they have been located under
dn=sambaDomainName=MEGANET2,dc=abmas,dc=biz. They could just as well be located under the rdn
cn=NextFreeUnixId.
The steps in the process involve changes from the network configuration
shown in .
Before implementing the following steps, you must have completed the network implementation shown
in that chapter. If you are starting with newly installed Linux servers, you must complete
the steps shown in before commencing
at :
OpenLDAP Server Configurationnss_ldappam_ldapopenldap
Confirm that the packages shown in are installed on your system.
Required OpenLDAP Linux PackagesSUSE Linux 8.xSUSE Linux 9.xRed Hat Linuxnss_ldapnss_ldapnss_ldappam_ldappam_ldappam_ldapopenldap2openldap2openldapopenldap2-clientopenldap2-client
Samba-3 and OpenLDAP will have a degree of inter-dependence that is unavoidable. The method
for boot-strapping the LDAP and Samba-3 configuration is relatively straight forward. If you
follow these guidelines, the resulting system should work fine.
Implementing the OpenLDAP Server/etc/openldap/slapd.conf
Install the file shown in in the directory
/etc/openldap.
The rootpw value is an enrypted password string that can be
generated by executing the slappasswd command.
/data/ldapgroup accountuser account
Remove all files from the directory /data/ldap, making certain that
the directory exists with permissions:
&rootprompt; ls -al /data | grep ldap
drwx------ 2 ldap ldap 48 Dec 15 22:11 ldap
This may require you to add a user and a group account for LDAP if they do not exist.
DB_CONFIG
Install the file shown in in the directory
/data/ldap. In the event that this file is added after ldap
has been started, it is possible to cause the new settings to take effect by shutting down
the LDAP server, executing the db_recover command inside the
/data/ldap directory, and then restarting the LDAP server.
syslog
Performance logging can be enabled and should preferably be sent to a file on
a file system that is large enough to handle significantly sized logs. To enable
the logging at a verbose level to permit detailed analysis uncomment the entry in
the /etc/openldap/slapd.conf shown as loglevel 256.
Edit the /etc/syslog.conf file to add the following at the end
of the file:
local4.* -/data/ldap/log/openldap.log
Note: The path /data/ldap/log should be set a a location
that is convenient and that can store a large volume of data.
LDAP DB_CONFIG File
set_cachesize 0 150000000 1
set_lg_regionmax 262144
set_lg_bsize 2097152
#set_lg_dir /var/log/bdb
set_flags DB_LOG_AUTOREMOVE
LDAP Master Configuration File &smbmdash; <filename>/etc/openldap/slapd.conf</filename> Part A
include /etc/openldap/schema/core.schema
include /etc/openldap/schema/cosine.schema
include /etc/openldap/schema/inetorgperson.schema
include /etc/openldap/schema/nis.schema
include /etc/openldap/schema/samba3.schema
pidfile /var/run/slapd/slapd.pid
argsfile /var/run/slapd/slapd.args
access to dn.base=""
by self write
by * auth
access to attr=userPassword,sambaLMPassword,sambaNTPassword
by self write
by * auth
access to attr=shadowLastChange
by self write
by * read
access to *
by * read
by anonymous auth
#loglevel 256
schemacheck on
idletimeout 30
backend bdb
database bdb
checkpoint 1024 5
cachesize 10000
suffix "dc=abmas,dc=biz"
rootdn "cn=Manager,dc=abmas,dc=biz"
# rootpw = not24get
rootpw {SSHA}86kTavd9Dw3FAz6qzWTrCOKX/c0Qe+UV
directory /data/ldap
LDAP Master Configuration File &smbmdash; <filename>/etc/openldap/slapd.conf</filename> Part B
# Indices to maintain
index objectClass eq
index cn pres,sub,eq
index sn pres,sub,eq
index uid pres,sub,eq
index displayName pres,sub,eq
index uidNumber eq
index gidNumber eq
index memberUID eq
index sambaSID eq
index sambaPrimaryGroupSID eq
index sambaDomainName eq
index default sub
PAM and NSS Client ConfigurationLDAPNSSPAM
The steps that follow involve configuration of LDAP, name service switch (NSS) LDAP-based resolution
of users and groups. Also, so that LDAP-based accounts can log onto the system, the steps ahead
configure the Pluggable Authentication Modules (PAM) to permit LDAP-based authentication.
Since you have chosen to put UNIX user and group accounts into the LDAP database, it is likely
that you may want to use them for UNIX system (Linux) local machine logons. This necessitates
correct configuration of the Pluggable Authentication
ModulesPluggable Authentication ModulesPAMpam_unix2.so
(PAM). The pam_ldap
open source package provides the PAM modules that most people would use. On SUSE Linux systems,
the pam_unix2.so module also has the ability to redirect authentication requests
through LDAP.
YaSTSUSE LinuxRed Hat Linuxauthconfig
You have chosen to configure these services by directly editing the system files but, of course, you
know that this configuration can be done using system tools provided by the Linux system vendor.
SUSE Linux has a facility in YaST (the system admin tool) through yastsystemldap-client that permits
configuration of SUSE Linux as an LDAP client. Red Hat Linux provides
the authconfig
tool for this.
Configuration of NSS and PAM/lib/libnss_ldap.so.2/etc/ldap.confnss_ldap
Execute the following command to find where the nss_ldap module
expects to find its control file:
&rootprompt; strings /lib/libnss_ldap.so.2 | grep conf
The preferred and usual location is /etc/ldap.conf.
On the server MASSIVE, install the file shown in
into the path that was obtained from the step above.
On the servers called BLDG1 and BLDG2, install the file shown in
into the path that was obtained from the step above.
Configuration File for NSS LDAP Support &smbmdash; <filename>/etc/ldap.conf</filename>
host 127.0.0.1
base dc=abmas,dc=biz
binddn cn=Manager,dc=abmas,dc=biz
bindpw not24get
timelimit 50
bind_timelimit 50
bind_policy hard
idle_timelimit 3600
pam_password exop
nss_base_passwd ou=People,dc=abmas,dc=biz?one
nss_base_shadow ou=People,dc=abmas,dc=biz?one
nss_base_group ou=Groups,dc=abmas,dc=biz?one
ssl off
Configuration File for NSS LDAP Clients Support &smbmdash; <filename>/etc/ldap.conf</filename>
host 172.16.0.1
base dc=abmas,dc=biz
binddn cn=Manager,dc=abmas,dc=biz
bindpw not24get
timelimit 50
bind_timelimit 50
bind_policy hard
idle_timelimit 3600
pam_password exop
nss_base_passwd ou=People,dc=abmas,dc=biz?one
nss_base_shadow ou=People,dc=abmas,dc=biz?one
nss_base_group ou=Groups,dc=abmas,dc=biz?one
ssl off
/etc/nsswitch.conf
Edit the NSS control file (/etc/nsswitch.conf) so that the lines that
control user and group resolution will obtain information from the normal system files as
well as from ldap as follows:
passwd: files ldap
shadow: files ldap
group: files ldap
hosts: files dns wins
Later, when the LDAP database has been initialized and user and group accounts have been
added, you can validate resolution of the LDAP resolver process. The inclusion of
WINS-based hostname resolution is deliberate so that all MS Windows client hostnames can be
resolved to their IP addresses, whether or not they are DHCP clients.
Some Linux systems (Novell SUSE Linux in particular) add entries to the nsswitch.conf
file that may cause operational problems with the configuration methods adopted in this book. It is
advisable to comment out the entries passwd_compat and group_compat
where they are found in this file.
Even at the risk of overstating the issue, incorrect and inappropriate configuration of the
nsswitch.conf file is a significant cause of operational problems with LDAP.
pam_unix2.souse_ldap
For PAM LDAP configuration on this SUSE Linux 9.0 system, the simplest solution is to edit the following
files in the /etc/pam.d directory:
login, password, samba, sshd.
In each file, locate every entry that has the pam_unix2.so entry and add to the
line the entry use_ldap as shown for the
login module in
this example:
#%PAM-1.0
auth requisite pam_unix2.so nullok use_ldap #set_secrpc
auth required pam_securetty.so
auth required pam_nologin.so
#auth required pam_homecheck.so
auth required pam_env.so
auth required pam_mail.so
account required pam_unix2.so use_ldap
password required pam_pwcheck.s nullok
password required pam_unix2.so nullok use_first_pass \
use_authtok use_ldap
session required pam_unix2.so none use_ldap # debug or trace
session required pam_limits.so
pam_ldap.so
On other Linux systems that do not have an LDAP-enabled pam_unix2.so module,
you must edit these files by adding the pam_ldap.so modules as shown here:
#%PAM-1.0
auth required pam_securetty.so
auth required pam_nologin.so
auth sufficient pam_ldap.so
auth required pam_unix2.so nullok try_first_pass #set_secrpc
account sufficient pam_ldap.so
account required pam_unix2.so
password required pam_pwcheck.so nullok
password required pam_ldap.so use_first_pass use_authtok
password required pam_unix2.so nullok use_first_pass use_authtok
session required pam_unix2.so none # debug or trace
session required pam_limits.so
session required pam_env.so
session optional pam_mail.so
This example does have the LDAP-enabled pam_unix2.so, but simply
demonstrates the use of the pam_ldap.so module. You can use either
implementation, but if the pam_unix2.so on your system supports
LDAP, you probably want to use it, rather than add an additional module.
Samba-3 PDC ConfigurationSamba RPM Packages
Verify that the Samba-3.0.15 (or later) packages are installed on each SUSE Linux server
before following the steps below. If Samba-3.0.15 (or later) is not installed, you have the
choice to either build your own or to obtain the packages from a dependable source.
Packages for SUSE Linux 8.x, 9.x and SUSE Linux Enterprise Server 9, as well as for
Red Hat Fedora Core and Red Hat Enterprise Linux Server 3 and 4 are included on the CD-ROM that
is included at the back of this book.
Configuration of PDC Called: <constant>MASSIVE</constant>
Install the files in ,
, ,
and into the /etc/samba/
directory. The three files should be added together to form the &smb.conf;
master file. It is a good practice to call this file something like
smb.conf.master, and then to perform all file edits
on the master file. The operational &smb.conf; is then generated as shown in
the next step.
testparm
Create and verify the contents of the &smb.conf; file that is generated by:
&rootprompt; testparm -s smb.conf.master > smb.conf
Immediately follow this with the following:
&rootprompt; testparm
The output that is created should be free from errors, as shown here:
Load smb config files from /etc/samba/smb.conf
Processing section "[accounts]"
Processing section "[service]"
Processing section "[pidata]"
Processing section "[homes]"
Processing section "[printers]"
Processing section "[apps]"
Processing section "[netlogon]"
Processing section "[profiles]"
Processing section "[profdata]"
Processing section "[print$]"
Loaded services file OK.
Server role: ROLE_DOMAIN_PDC
Press enter to see a dump of your service definitions
Delete all run-time files from prior Samba operation by executing (for SUSE
Linux):
&rootprompt; rm /etc/samba/*tdb
&rootprompt; rm /var/lib/samba/*tdb
&rootprompt; rm /var/lib/samba/*dat
&rootprompt; rm /var/log/samba/*
secrets.tdbsmbpasswd
Samba-3 communicates with the LDAP server. The password that it uses to
authenticate to the LDAP server must be stored in the secrets.tdb
file. Execute the following to create the new secrets.tdb files
and store the password for the LDAP Manager:
&rootprompt; smbpasswd -w not24get
The expected output from this command is:
Setting stored password for "cn=Manager,dc=abmas,dc=biz" in secrets.tdb
smbdnetgetlocalsid
Samba-3 generates a Windows Security Identifier only when smbd
has been started. For this reason, you start Samba. After a few seconds delay,
execute:
&rootprompt; smbclient -L localhost -U%
&rootprompt; net getlocalsid
A report such as the following means that the Domain Security Identifier (SID) has not yet
been written to the secrets.tdb or to the LDAP backend:
[2005/03/03 23:19:34, 0] lib/smbldap.c:smbldap_connect_system(852)
failed to bind to server ldap://massive.abmas.biz
with dn="cn=Manager,dc=abmas,dc=biz" Error: Can't contact LDAP server
(unknown)
[2005/03/03 23:19:48, 0] lib/smbldap.c:smbldap_search_suffix(1169)
smbldap_search_suffix: Problem during the LDAP search:
(unknown) (Timed out)
The attempt to read the SID will attempt to bind to the LDAP server. Because the LDAP server
is not running this operation will fail by way of a time out, as shown above. This is
normal output, do not worry about this error message. When the Domain has been created and
written to the secrets.tdb file, the output should look like this:
SID for domain MASSIVE is: S-1-5-21-3504140859-1010554828-2431957765
If, after a short delay (a few seconds), the Domain SID has still not been written to
the secrets.tdb file, it is necessary to investigate what
may be mis-configured. In this case, carefully check the &smb.conf; file for typographical
errors (the most common problem). The use of the testparm is highly
recommended to validate the contents of this file.
When a positive Domain SID has been reported, stop Samba.
NFS server/etc/exportsBDCrsync
Configure the NFS server for your Linux system. So you can complete the steps that
follow, enter into the /etc/exports the following entry:
/home *(rw,root_squash,sync)
This permits the user home directories to be used on the BDC servers for testing
purposes. You, of course, decide what is the best way for your site to distribute
data drives, as well as creating suitable backup and restore procedures for Abmas Inc.
I'd strongly recommend that for normal operation the BDC is completely independent
of the PDC. rsync is a useful tool here as it resembles the NT replication service quite
closely. If you do use NFS, do not forget to start the NFS server as follows:
&rootprompt; rcnfsserver start
Your Samba-3 PDC is now ready to communicate with the LDAP password backend. Let's get on with
configuration of the LDAP server.
LDAP Based &smb.conf; File, Server: MASSIVE &smbmdash; global Section: Part AGlobal parametersLOCALEMEGANET2MASSIVEeth1, loYesldapsam:ldap://massive.abmas.bizYes/etc/samba/smbusers10/var/log/samba/%m50139 445wins bcast hostsYesCUPSNo/opt/IDEALX/sbin/smbldap-useradd -m "%u"/opt/IDEALX/sbin/smbldap-userdel "%u"/opt/IDEALX/sbin/smbldap-groupadd -p "%g"/opt/IDEALX/sbin/smbldap-groupdel "%g"/opt/IDEALX/sbin/smbldap-groupmod -m "%u" "%g"/opt/IDEALX/sbin/smbldap-groupmod -x "%u" "%g"/opt/IDEALX/sbin/smbldap-usermod -g "%g" "%u"/opt/IDEALX/sbin/smbldap-useradd -w "%u"LDAP Based &smb.conf; File, Server: MASSIVE &smbmdash; global Section: Part Bscripts\logon.bat\\%L\profiles\%UX:YesYesYesdc=abmas,dc=bizou=Peopleou=Peopleou=Groupsou=Idmapcn=Manager,dc=abmas,dc=bizldap:ldap://massive.abmas.biz10000-2000010000-20000Yescupsroot, chrisrInstall and Configure Idealx smbldap-tools ScriptsIdealxsmbldap-tools
The Idealx scripts, or equivalent, are necessary to permit Samba-3 to manage accounts
on the LDAP server. You have chosen the Idealx scripts since they are the best known
LDAP configuration scripts. The use of these scripts will help avoid the necessity
to create custom scripts. It is easy to download them from the Idealx
Web Site. The tarball may
be directly downloaded
for this site, also. Alternately, you may obtain the
smbldap-tools-0.8.8-3.src.rpm
file that may be used to build an install-able RPM package for your Linux system.
The smbldap-tools scripts can be installed in any convenient directory of your choice, in which case you must
change the path to them in your &smb.conf; file on the PDC (MASSIVE).
The smbldap-tools are located in /opt/IDEALX/sbin.
The scripts are not needed on BDC machines because all LDAP updates are handled by
the PDC alone.
Installation of smbldap-tools from the tarball
To perform a manual installation of the smbldap-tools scripts the following procedure may be used:
Idealx smbldap-tools Configuration
Create the /opt/IDEALX/sbin directory, and set its permissions
and ownership as shown here:
&rootprompt; mkdir -p /opt/IDEALX/sbin
&rootprompt; chown root.root /opt/IDEALX/sbin
&rootprompt; chmod 755 /opt/IDEALX/sbin
&rootprompt; mkdir -p /etc/smbldap-tools
&rootprompt; chown root.root /etc/smbldap-tools
&rootprompt; chmod 755 /etc/smbldap-tools
If you wish to use the downloaded tarball, unpack the smbldap-tools in a suitable temporary location.
Change into either the directory extracted from the tarball, or else into the smbldap-tools
directory in your /usr/share/doc/packages directory tree.
Copy all the smbldap-* and the configure.pl files into the
/opt/IDEALX/sbin directory, as shown here:
&rootprompt; cd smbldap-tools-0.8.8/
&rootprompt; cp smbldap-* configure.pl *pm /opt/IDEALX/sbin/
&rootprompt; cp smbldap*conf /etc/smbldap-tools/
&rootprompt; chmod 750 /opt/IDEALX/sbin/configure.pl
&rootprompt; chmod 640 /etc/smbldap-tools/smbldap.conf
&rootprompt; chmod 600 /etc/smbldap-tools/smbldap_bind.conf
The smbldap-tools scripts master control file must now be configured.
Change to the /opt/IDEALX/sbin directory, then edit the
smbldap_tools.pm to affect the changes
shown here:
...
# ugly funcs using global variables and spawning openldap clients
my $smbldap_conf="/etc/smbldap-tools/smbldap.conf";
my $smbldap_bind_conf="/etc/smbldap-tools/smbldap_bind.conf";
...
To complete the configuration of the smbldap-tools, set the permissions and ownership
by executing the following commands:
&rootprompt; chown -R root:root /opt/IDEALX/sbin/*
&rootprompt; chmod 755 /opt/IDEALX/sbin/smbldap-*
&rootprompt; chmod 640 /opt/IDEALX/sbin/smb*pm
The smbldap-tools scripts are now ready for the configuration step outlined in
Configuration of smbldap-tools.
Installing smbldap-tools from the RPM Package
In the event that you have elected to use the RPM package provided by Idealx, download the
source RPM smbldap-tools-0.8.8-3.src.rpm, then follow the following procedure:
Installation of smbldap-tools from RPM
Install the source RPM that has been downloaded as follows:
&rootprompt; rpm -i smbldap-tools-0.8.8-3.src.rpm
Change into the directory in which the SPEC files are located. On SUSE Linux:
&rootprompt; cd /usr/src/packages/SPECS
On Red Hat Linux systems:
&rootprompt; cd /usr/src/redhat/SPECS
Edit the smbldap-tools.spec file to change the value of the
_sysconfig macro as shown here:
%define _prefix /opt/IDEALX
%define _sysconfdir /etc
Note: Any suitable directory can be specified.
Build the package by executing:
&rootprompt; rpmbuild -ba -v smbldap-tools.spec
A build process that has completed without error will place the install-able binary
files in the directory ../RPMS/noarch.
Install the binary package by executing:
&rootprompt; rpm -Uvh ../RPMS/noarch/smbldap-tools-0.8.8-3.noarch.rpm
The Idealx scripts should now be ready for configuration using the steps outlined in
Configuration of smbldap-tools.
Configuration of smbldap-tools
Prior to use the smbldap-tools must be configured to match the settings in the &smb.conf; file
and to match the settings in the /etc/openldap/slapd.conf file. The assumption
is made that the &smb.conf; file has correct contents. The following procedure will ensure that
this is completed correctly:
The smbldap-tools require that the netbios name (machine name) of the Samba server be included
in the &smb.conf; file.
Configuration of <filename>smbldap.conf</filename>
Change into the directory that contains the configure.pl script.
&rootprompt; cd /opt/IDEALX/sbin
Execute the configure.pl script as follows:
&rootprompt; ./configure.pl
The interactive use of this script for the PDC is demonstrated here:
Unrecognized escape \p passed through at ./configure.pl line 194.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
smbldap-tools script configuration
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Before starting, check
. if your samba controller is up and running.
. if the domain SID is defined (you can get it with the 'net getlocalsid')
. you can leave the configuration using the Crtl-c key combination
. empty value can be set with the "." character
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Looking for configuration files...
Samba Config File Location [/etc/samba/smb.conf] >
smbldap Config file Location (global parameters)
[/etc/smbldap-tools/smbldap.conf] >
smbldap Config file Location (bind parameters)
[/etc/smbldap-tools/smbldap_bind.conf] >
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Let's start configuring the smbldap-tools scripts ...
. workgroup name: name of the domain Samba act as a PDC
workgroup name [MEGANET2] >
. netbios name: netbios name of the samba controller
netbios name [MASSIVE] >
. logon drive: local path to which the home directory
will be connected (for NT Workstations). Ex: 'H:'
logon drive [X:] >
. logon home: home directory location (for Win95/98 or NT Workstation).
(use %U as username) Ex:'\\MASSIVE\home\%U'
logon home (leave blank if you don't want homeDirectory)
[\\MASSIVE\home\%U] > \\MASSIVE\%U
. logon path: directory where roaming profiles are stored.
Ex:'\\MASSIVE\profiles\%U'
logon path (leave blank if you don't want roaming profile)
[\\MASSIVE\profiles\%U] >
. home directory prefix (use %U as username)
[/home/%U] > /home/users/%U
. default user netlogon script (use %U as username)
[%U.cmd] > scripts\login.cmd
default password validation time (time in days) [45] > 0
. ldap suffix [dc=abmas,dc=biz] >
. ldap group suffix [ou=Groups] >
. ldap user suffix [ou=People] >
. ldap machine suffix [ou=People] >
. Idmap suffix [ou=Idmap] >
. sambaUnixIdPooldn: object where you want to store the next uidNumber
and gidNumber available for new users and groups
sambaUnixIdPooldn object (relative to ${suffix})
[cn=NextFreeUnixId] > sambaDomainName=MEGANET2
. ldap master server: IP address or DNS name
of the master (writable) ldap server
Use of uninitialized value in scalar chomp at ./configure.pl
line 138, <STDIN> line 17.
Use of uninitialized value in hash element at ./configure.pl
line 140, <STDIN> line 17.
Use of uninitialized value in concatenation (.) or string at
./configure.pl line 144, <STDIN> line 17.
Use of uninitialized value in string at ./configure.pl
line 145, <STDIN> line 17.
ldap master server [] > 127.0.0.1
. ldap master port [389] >
. ldap master bind dn [cn=Manager,dc=abmas,dc=biz] >
. ldap master bind password [] >
. ldap slave server: IP address or DNS name of the slave
ldap server: can also be the master one
Use of uninitialized value in scalar chomp at ./configure.pl
line 138, <STDIN> line 21.
Use of uninitialized value in hash element at ./configure.pl
line 140, <STDIN> line 21.
Use of uninitialized value in concatenation (.) or string at
./configure.pl line 144, <STDIN> line 21.
Use of uninitialized value in string at ./configure.pl line 145,
<STDIN> line 21.
ldap slave server [] > 127.0.0.1
. ldap slave port [389] >
. ldap slave bind dn [cn=Manager,dc=abmas,dc=biz] >
. ldap slave bind password [] >
. ldap tls support (1/0) [0] >
. SID for domain MEGANET2: SID of the domain
(can be obtained with 'net getlocalsid MASSIVE')
SID for domain MEGANET2
[S-1-5-21-3504140859-1010554828-2431957765] >
. unix password encryption: encryption used for unix passwords
unix password encryption
(CRYPT, MD5, SMD5, SSHA, SHA) [SSHA] > MD5
. default user gidNumber [513] >
. default computer gidNumber [515] >
. default login shell [/bin/bash] >
. default domain name to append to mail address [] > abmas.biz
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
backup old configuration files:
/etc/smbldap-tools/smbldap.conf->
etc/smbldap-tools/smbldap.conf.old
/etc/smbldap-tools/smbldap_bind.conf->
etc/smbldap-tools/smbldap_bind.conf.old
writing new configuration file:
/etc/smbldap-tools/smbldap.conf done.
/etc/smbldap-tools/smbldap_bind.conf done.
Since a slave LDAP server has not been configured it is necessary to specify the IP
address of the master LDAP server for both the master and the slave configuration
prompts.
Change to the directory that contains the smbldap.conf file
then verify its contents.
The smbldap-tools are now ready for use.
LDAP Initialization and Creation of User and Group Accounts
The LDAP database must be populated with well-known Windows Domain user accounts and Domain Group
accounts before Samba can be used. The following procedures step you through the process.
At this time, Samba-3 requires that on a PDC all UNIX (Posix) group accounts that are
mapped (linked) to Windows Domain Group accounts must be in the LDAP database. It does not
hurt to have UNIX user and group accounts in both the system files as well as in the LDAP
database. From a UNIX system perspective, the NSS resolver checks system files before
referring to LDAP. If the UNIX system can resolve (find) an account in the system file, it
does not need to ask LDAP.
Addition of an account to the LDAP backend can be done in a number of ways:
NIS/etc/passwdPosix accountspdbeditSambaSamAccountPosixAccount
If you always have a user account in the /etc/passwd on every
server or in a NIS(+) backend, it is not necessary to add Posix accounts for them in
LDAP. In this case, you can add Windows Domain user accounts using the
pdbedit utility. Use of this tool from the command line adds the
SambaSamAccount entry for the user, but does not add the PosixAccount entry for the user.
If you decide that it is probably a good idea to add both the PosixAccount attributes
as well as the SambaSamAccount attributes for each user, then a suitable script is needed.
In the example system you are installing in this exercise, you are making use of the
Idealx smbldap-tools scripts. A copy of these tools, pre-configured for this system,
is included on the enclosed CD-ROM under Chap06/Tools.
Idealxsmbldap-tools
If you wish to have more control over how the LDAP database is initialized or
want not to use the Idealx smbldap-tools, you should refer to .
smbldap-populate
The following steps initialize the LDAP database, and then you can add user and group
accounts that Samba can use. You use the smbldap-populate to
seed the LDAP database. You then manually add the accounts shown in .
The list of users does not cover all 500 network users; it provides examples only.
LDAPdatabasedirectoryPeople containerdirectoryComputers container
In the following examples, as the LDAP database is initialized, we do create a container
for Computer (machine) accounts. In the Samba-3 &smb.conf; files, specific use is made
of the People container, not the Computers container, for domain member accounts. This is not a
mistake; it is a deliberate action that is necessitated by the fact that the resolution of
a machine (computer) account to a UID is done via NSS. The only way this can be handled is
using the NSS (/etc/nsswitch.conf) entry for passwd
which is resolved using the nss_ldap library. The configuration file for
the nss_ldap library is the file /etc/ldap.conf that
provides only one possible LDAP search command that is specified by the entry called
nss_base_passwd. This means that the search path must take into account
the directory structure so that the LDAP search will commence at a level that is above
both the Computers container and the Users (or People) container. If this is done, it is
necessary to use a search that will descend the directory tree so that the machine account
can be found. Alternately, by placing all machine accounts in the People container, we
are able to side-step this limitation. This is the simpler solution that has been adopted
in this chapter.
Abmas Network Users and GroupsAccount NameTypeIDPasswordRobert JordanUserbobjn3v3r2l8Stanley SorokaUserstansimpl13dst4rChristine RobersonUserchrisrS9n0nw4llMary VortexisUsermaryvkw13t0n3AccountsGroupAccountsFinancesGroupFinancesInsuranceGroupPIOps
Validation of Configuration
Start the LDAP server by executing:
&rootprompt; rcldap start
Starting ldap-server done
Change to the /opt/IDEALX/sbin directory.
Execute the script that will populate the LDAP database as shown here:
&rootprompt; ./smbldap-populate -a root -k 0 -m 0
The expected output from this is:
Using workgroup name from smb.conf: sambaDomainName=MEGANET2
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
=> Warning: you must update smbldap.conf configuration file to :
=> sambaUnixIdPooldn parameter must be set
to "sambaDomainName=MEGANET2,dc=abmas,dc=biz"
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Using builtin directory structure
adding new entry: dc=abmas,dc=biz
adding new entry: ou=People,dc=abmas,dc=biz
adding new entry: ou=Groups,dc=abmas,dc=biz
entry ou=People,dc=abmas,dc=biz already exist.
adding new entry: ou=Idmap,dc=abmas,dc=biz
adding new entry: sambaDomainName=MEGANET2,dc=abmas,dc=biz
adding new entry: uid=root,ou=People,dc=abmas,dc=biz
adding new entry: uid=nobody,ou=People,dc=abmas,dc=biz
adding new entry: cn=Domain Admins,ou=Groups,dc=abmas,dc=biz
adding new entry: cn=Domain Users,ou=Groups,dc=abmas,dc=biz
adding new entry: cn=Domain Guests,ou=Groups,dc=abmas,dc=biz
adding new entry: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
adding new entry: cn=Administrators,ou=Groups,dc=abmas,dc=biz
adding new entry: cn=Print Operators,ou=Groups,dc=abmas,dc=biz
adding new entry: cn=Backup Operators,ou=Groups,dc=abmas,dc=biz
adding new entry: cn=Replicators,ou=Groups,dc=abmas,dc=biz
Edit the /etc/smbldap-tools/smbldap.conf file so that the following
information is changed from:
# Where to store next uidNumber and gidNumber available
sambaUnixIdPooldn="cn=NextFreeUnixId,${suffix}"
to read, after modification:
# Where to store next uidNumber and gidNumber available
#sambaUnixIdPooldn="cn=NextFreeUnixId,${suffix}"
sambaUnixIdPooldn="sambaDomainName=MEGANET2,dc=abmas,dc=biz"
It is necessary to restart the LDAP server as shown here:
&rootprompt; rcldap restart
Shutting down ldap-server done
Starting ldap-server done
slapcat
So that we can use a global IDMAP repository the LDAP directory must have a container object for IDMAP data.
There are several ways you can check that your LDAP database is able to receive IDMAP information. One of
the simplest is to execute:
&rootprompt; slapcat | grep -i idmap
dn: ou=Idmap,dc=abmas,dc=biz
ou: idmap
ldapadd
If the execution of this command does not return IDMAP entries, you need to create an LDIF
template file (see ). You can add the required entries using
the following command:
&rootprompt; ldapadd -x -D "cn=Manager,dc=abmas,dc=biz" \
-w not24get < /etc/openldap/idmap.LDIF
Samba automatically populates this LDAP directory container when it needs to.
slapcat
It looks like all has gone well, as expected. Let's confirm that this is the case
by running a few tests. First we check the contents of the database directly
by running slapcat as follows (the output has been cut down):
&rootprompt; slapcat
dn: dc=abmas,dc=biz
objectClass: dcObject
objectClass: organization
dc: abmas
o: abmas
structuralObjectClass: organization
entryUUID: 5ab02bf6-c536-1027-9d29-b1f32350fb43
creatorsName: cn=Manager,dc=abmas,dc=biz
createTimestamp: 20031217234200Z
entryCSN: 2003121723:42:00Z#0x0001#0#0000
modifiersName: cn=Manager,dc=abmas,dc=biz
modifyTimestamp: 20031217234200Z
...
dn: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
objectClass: posixGroup
objectClass: sambaGroupMapping
gidNumber: 553
cn: Domain Computers
description: Netbios Domain Computers accounts
sambaSID: S-1-5-21-3504140859-1010554828-2431957765-553
sambaGroupType: 2
displayName: Domain Computers
structuralObjectClass: posixGroup
entryUUID: 5e0a41d8-c536-1027-9d3b-b1f32350fb43
creatorsName: cn=Manager,dc=abmas,dc=biz
createTimestamp: 20031217234206Z
entryCSN: 2003121723:42:06Z#0x0002#0#0000
modifiersName: cn=Manager,dc=abmas,dc=biz
modifyTimestamp: 20031217234206Z
This looks good so far.
ldapsearch
The next step is to prove that the LDAP server is running and responds to a
search request. Execute the following as shown (output has been cut to save space):
&rootprompt; ldapsearch -x -b "dc=abmas,dc=biz" "(ObjectClass=*)"
# extended LDIF
#
# LDAPv3
# base <dc=abmas,dc=biz> with scope sub
# filter: (ObjectClass=*)
# requesting: ALL
#
# abmas.biz
dn: dc=abmas,dc=biz
objectClass: dcObject
objectClass: organization
dc: abmas
o: abmas
# People, abmas.biz
dn: ou=People,dc=abmas,dc=biz
objectClass: organizationalUnit
ou: People
...
# Domain Computers, Groups, abmas.biz
dn: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
objectClass: posixGroup
objectClass: sambaGroupMapping
gidNumber: 553
cn: Domain Computers
description: Netbios Domain Computers accounts
sambaSID: S-1-5-21-3504140859-1010554828-2431957765-553
sambaGroupType: 2
displayName: Domain Computers
# search result
search: 2
result: 0 Success
# numResponses: 20
# numEntries: 19
Good. It is all working just fine.
getent
You must now make certain that the NSS resolver can interrogate LDAP also.
Execute the following commands:
&rootprompt; getent passwd | grep root
root:x:998:512:Netbios Domain Administrator:/home:/bin/false
&rootprompt; getent group | grep Domain
Domain Admins:x:512:root
Domain Users:x:513:
Domain Guests:x:514:
Domain Computers:x:553:
nss_ldap
This demonstrates that the nss_ldap library is functioning
as it should. If these two steps fail to produce this information refer to
for diagnostic procedures that can be followed to
isolate the cause of the problem. Proceed to the next step only when the steps
above have been successfully completed.
smbldap-useraddsmbldap-passwdsmbpasswd
Our database is now ready for the addition of network users. For each user for
whom an account must be created, execute the following:
&rootprompt; ./smbldap-useradd -m -a username
&rootprompt; ./smbldap-passwd username
Changing password for username
New password : XXXXXXXX
Retype new password : XXXXXXXX
&rootprompt; smbpasswd username
New SMB password: XXXXXXXX
Retype new SMB password: XXXXXXXX
Where username is the login ID for each user.
getent
Now verify that the UNIX (Posix) accounts can be resolved via NSS by executing the
following:
&rootprompt; getent passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/bin/bash
...
root:x:0:512:Netbios Domain Administrator:/home:/bin/false
nobody:x:999:514:nobody:/dev/null:/bin/false
bobj:x:1000:513:System User:/home/bobj:/bin/bash
stans:x:1001:513:System User:/home/stans:/bin/bash
chrisr:x:1002:513:System User:/home/chrisr:/bin/bash
maryv:x:1003:513:System User:/home/maryv:/bin/bash
This demonstrates that user account resolution via LDAP is working.
This step will determine
&rootprompt; id chrisr
uid=1002(chrisr) gid=513(Domain Users) groups=513(Domain Users)
This confirms that the UNIX (Posix) user account information can be resolved from LDAP
by system tools that make a getentpw() system call.
smbldap-usermod
The 'root' account must have UID=0, if not this means that operations conducted from
a Windows client using tools such as the Domain User Manager fails under UNIX because
the management of user and group accounts requires that the UID=0. Additionally, it is
a good idea to make certain that no matter how 'root' account credentials are resolved
that the home directory and shell are valid. You decide to effect this immediately
as demonstrated here:
&rootprompt; cd /opt/IDEALX/sbin
&rootprompt; ./smbldap-usermod -u 0 -d /root -s /bin/bash root
Verify that the changes just made to the root account were
accepted by executing:
&rootprompt; getent passwd | grep root
root:x:0:0:root:/root:/bin/bash
root:x:0:512:Netbios Domain Administrator:/root:/bin/bash
This demonstrates that the changes were accepted.
Make certain that a home directory has been created for every user by listing the
directories in /home as follows:
&rootprompt; ls -al /home
drwxr-xr-x 8 root root 176 Dec 17 18:50 ./
drwxr-xr-x 21 root root 560 Dec 15 22:19 ../
drwx------ 7 bobj Domain Users 568 Dec 17 01:16 bobj/
drwx------ 7 chrisr Domain Users 568 Dec 17 01:19 chrisr/
drwx------ 7 maryv Domain Users 568 Dec 17 01:27 maryv/
drwx------ 7 stans Domain Users 568 Dec 17 01:43 stans/
This is precisely what we want to see.
ldapsampdbedit
The final validation step involves making certain that Samba-3 can obtain the user
accounts from the LDAP ldapsam passwd backend. Execute the following command as shown:
&rootprompt; pdbedit -Lv chrisr
Unix username: chrisr
NT username: chrisr
Account Flags: [U ]
User SID: S-1-5-21-3504140859-1010554828-2431957765-3004
Primary Group SID: S-1-5-21-3504140859-1010554828-2431957765-513
Full Name: System User
Home Directory: \\MASSIVE\homes
HomeDir Drive: H:
Logon Script: scripts\login.cmd
Profile Path: \\MASSIVE\profiles\chrisr
Domain: MEGANET2
Account desc: System User
Workstations:
Munged dial:
Logon time: 0
Logoff time: Mon, 18 Jan 2038 20:14:07 GMT
Kickoff time: Mon, 18 Jan 2038 20:14:07 GMT
Password last set: Wed, 17 Dec 2003 17:17:40 GMT
Password can change: Wed, 17 Dec 2003 17:17:40 GMT
Password must change: Mon, 18 Jan 2038 20:14:07 GMT
Last bad password : 0
Bad password count : 0
Logon hours : FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
This looks good. Of course, you fully expected that it would all work, didn't you?
smbldap-groupadd
Now you add the group accounts that are used on the Abmas network. Execute
the following exactly as shown:
&rootprompt; ./smbldap-groupadd -a Accounts
&rootprompt; ./smbldap-groupadd -a Finances
&rootprompt; ./smbldap-groupadd -a PIOps
The addition of groups does not involve keyboard interaction, so the lack of console
output is of no concern.
getent
You really do want to confirm that UNIX group resolution from LDAP is functioning
as it should. Let's do this as shown here:
&rootprompt; getent group
...
Domain Admins:x:512:root
Domain Users:x:513:bobj,stans,chrisr,maryv
Domain Guests:x:514:
...
Accounts:x:1000:
Finances:x:1001:
PIOps:x:1002:
The well-known special accounts (Domain Admins, Domain Users, Domain Guests), as well
as our own site-specific group accounts, are correctly listed. This is looking good.
netgroupmaplist
The final step we need to validate is that Samba can see all the Windows Domain Groups
and that they are correctly mapped to the respective UNIX group account. To do this,
just execute the following command:
&rootprompt; net groupmap list
Domain Admins (S-1-5-21-3504140859-...-2431957765-512) -> Domain Admins
Domain Users (S-1-5-21-3504140859-...-2431957765-513) -> Domain Users
Domain Guests (S-1-5-21-3504140859-...-2431957765-514) -> Domain Guests
...
Accounts (S-1-5-21-3504140859-1010554828-2431957765-3001) -> Accounts
Finances (S-1-5-21-3504140859-1010554828-2431957765-3003) -> Finances
PIOps (S-1-5-21-3504140859-1010554828-2431957765-3005) -> PIOps
This is looking good. Congratulations &smbmdash; it works! Note that in the above output
the lines where shortened by replacing the middle value (1010554828) of the SID with the
ellipsis (...).
The server you have so carefully built is now ready for another important step. You
start the Samba-3 server and validate its operation. Execute the following to render all
the processes needed fully operative so that, on system reboot, they are automatically
started:
&rootprompt; chkconfig named on
&rootprompt; chkconfig dhcpd on
&rootprompt; chkconfig ldap on
&rootprompt; chkconfig nmb on
&rootprompt; chkconfig smb on
&rootprompt; chkconfig winbind on
&rootprompt; rcnmb start
&rootprompt; rcsmb start
&rootprompt; rcwinbind start
The next step might seem a little odd at this point, but take note that you are about to
start winbindd which must be able to authenticate to the PDC via the
localhost interface with the smbd process. This account can be
easily created by joining the PDC to the Domain by executing the following command:
&rootprompt; net rpc join -S MASSIVE -U root%not24get
Note: Before executing this command on the PDC both nmbd and
smbd must be started so that the net command
can communicate with smbd. The expected output is:
Joined domain MEGANET2.
This indicates that the Domain security account for the PDC has been correctly created.
At this time it is necessary to restart winbindd so that it can
correctly authenticate to the PDC. The following command achieves that:
&rootprompt; rcwinbind restart
smbclient
You may now check Samba-3 operation as follows:
&rootprompt; smbclient -L massive -U%
Sharename Type Comment
--------- ---- -------
IPC$ IPC IPC Service (Samba 3.0.15)
accounts Disk Accounting Files
service Disk Financial Services Files
pidata Disk Property Insurance Files
apps Disk Application Files
netlogon Disk Network Logon Service
profiles Disk Profile Share
profdata Disk Profile Data Share
ADMIN$ IPC IPC Service (Samba 3.0.15)
Server Comment
--------- -------
MASSIVE Samba 3.0.15
Workgroup Master
--------- -------
MEGANET2 MASSIVE
This shows that an anonymous connection is working.
For your finale, let's try an authenticated connection. Follow this as shown:
&rootprompt; smbclient //massive/bobj -Ubobj%n3v3r2l8
smb: \> dir
. D 0 Wed Dec 17 01:16:19 2003
.. D 0 Wed Dec 17 19:04:42 2003
bin D 0 Tue Sep 2 04:00:57 2003
Documents D 0 Sun Nov 30 07:28:20 2003
public_html D 0 Sun Nov 30 07:28:20 2003
.urlview H 311 Fri Jul 7 06:55:35 2000
.dvipsrc H 208 Fri Nov 17 11:22:02 1995
57681 blocks of size 524288. 57128 blocks available
smb: \> q
Well done. All is working fine.
The server MASSIVE is now configured, and it is time to move onto the next task.
Printer ConfigurationCUPS
The configuration for Samba-3 to enable CUPS raw-print-through printing has already been
taken care of in the &smb.conf; file. The only preparation needed for
smart
printing to be possible involves creation of the directories in which Samba-3 stores
Windows printing driver files.
Configuration of Raw Printers
Configure all network attached printers to have a fixed IP address.
Create an entry in the DNS database on the server MASSIVE
in both the forward lookup database for the zone abmas.biz.hosts
and in the reverse lookup database for the network segment that the printer is to
be located in. Example configuration files for similar zones were presented in
and in .
Follow the instructions in the printer manufacturers' manuals to permit printing
to port 9100. Use any other port the manufacturer specifies for direct mode,
raw printing. This allows the CUPS spooler to print using raw mode protocols.
CUPSraw printinglpadminCUPSqueue
Only on the server to which the printer is attached, configure the CUPS Print
Queues as follows:
&rootprompt; lpadmin -p printque
-v socket://printer-name.abmas.biz:9100 -E
print filter
This step creates the necessary print queue to use no assigned print filter. This
is ideal for raw printing, i.e., printing without use of filters.
The name printque is the name you have assigned for
the particular printer.
Print queues may not be enabled at creation. Make certain that the queues
you have just created are enabled by executing the following:
&rootprompt; /usr/bin/enable printque
Even though your print queue may be enabled, it is still possible that it
may not accept print jobs. A print queue will service incoming printing
requests only when configured to do so. Ensure that your print queue is
set to accept incoming jobs by executing the following commands:
&rootprompt; /usr/bin/accept printquemime type/etc/mime.convsapplication/octet-stream
Edit the file /etc/cups/mime.convs to uncomment the line:
application/octet-stream application/vnd.cups-raw 0 -
/etc/mime.types
Edit the file /etc/cups/mime.types to uncomment the line:
application/octet-stream
Refer to the CUPS printing manual for instructions regarding how to configure
CUPS so that print queues that reside on CUPS servers on remote networks
route print jobs to the print server that owns that queue. The default setting
on your CUPS server may automatically discover remotely installed printers and
may permit this functionality without requiring specific configuration.
The following action creates the necessary directory sub-system. Follow these
steps to printing heaven:
&rootprompt; mkdir -p /var/lib/samba/drivers/{W32ALPHA,W32MIPS,W32X86,WIN40}
&rootprompt; chown -R root.root /var/lib/samba/drivers
&rootprompt; chmod -R ug=rwx,o=rx /var/lib/samba/drivers
Samba-3 BDC ConfigurationConfiguration of BDC Called: <constant>BLDG1</constant>
Install the files in ,
, and
into the /etc/samba/ directory. The three files
should be added together to form the &smb.conf; file.
Verify the &smb.conf; file as in step 2 of .
Carefully follow the steps outlined in , taking
particular note to install the correct ldap.conf.
Verify that the NSS resolver is working. You may need to cycle the run level
to 1 and back to 5 before the NSS LDAP resolver functions. Follow these
commands:
&rootprompt; telinit 1
After the run level has been achieved, you are prompted to provide the
root password. Log on, and then execute:
&rootprompt; telinit 5
When the normal logon prompt appears, log into the system as
root
and then execute these commands:
&rootprompt; getent passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/bin/bash
daemon:x:2:2:Daemon:/sbin:/bin/bash
lp:x:4:7:Printing daemon:/var/spool/lpd:/bin/bash
mail:x:8:12:Mailer daemon:/var/spool/clientmqueue:/bin/false
...
root:x:0:512:Netbios Domain Administrator:/root:/bin/bash
nobody:x:999:514:nobody:/dev/null:/bin/false
bobj:x:1000:513:System User:/home/bobj:/bin/bash
stans:x:1001:513:System User:/home/stans:/bin/bash
chrisr:x:1002:513:System User:/home/chrisr:/bin/bash
maryv:x:1003:513:System User:/home/maryv:/bin/bash
vaioboss$:x:1005:553:vaioboss$:/dev/null:/bin/false
bldg1$:x:1006:553:bldg1$:/dev/null:/bin/false
This is the correct output. If the accounts that have UIDs above 512 are not shown, there is a problem.
getent
The next step in the verification process involves testing the operation of UNIX group
resolution via the NSS LDAP resolver. Execute these commands:
&rootprompt; getent group
root:x:0:
bin:x:1:daemon
daemon:x:2:
sys:x:3:
...
Domain Admins:x:512:root
Domain Users:x:513:bobj,stans,chrisr,maryv,jht
Domain Guests:x:514:
Administrators:x:544:
Users:x:545:
Guests:x:546:nobody
Power Users:x:547:
Account Operators:x:548:
Server Operators:x:549:
Print Operators:x:550:
Backup Operators:x:551:
Replicator:x:552:
Domain Computers:x:553:
Accounts:x:1000:
Finances:x:1001:
PIOps:x:1002:
This is also the correct and desired output, because it demonstrates that the LDAP client
is able to communicate correctly with the LDAP server
(MASSIVE).
smbpasswd
You must now set the LDAP administrative password into the
Samba-3 secrets.tdb
file by executing this command:
&rootprompt; smbpasswd -w not24get
Setting stored password for "cn=Manager,dc=abmas,dc=biz" in secrets.tdb
Now you must obtain the Domain Security Identifier from the PDC and store it into the
secrets.tdb file also. This step is not necessary with an LDAP
passdb backend because Samba-3 obtains the Domain SID from the
sambaDomain object it automatically stores in the LDAP backend. It does not hurt to
add the SID to the secrets.tdb, and if you wish to do so, this
command can achieve that:
&rootprompt; net rpc getsid MEGANET2
Storing SID S-1-5-21-3504140859-1010554828-2431957765 \
for Domain MEGANET2 in secrets.tdb
When configuring a Samba-3 BDC that has an LDAP backend, there is no need to take
any special action to join it to the Domain. However, winbind communicates with the
Domain Controller that is running on the localhost and must be able to authenticate,
thus requiring that the BDC should be joined to the Domain. The process of joining
the Domain creates the necessary authentication accounts.
To join the Samba BDC to the Domain execute the following:
&rootprompt; net rpc join -U root%not24get
Joined domain MEGANET2.
This indicates that the Domain security account for the BDC has been correctly created.
pdbedit
Verify that user and group account resolution works via Samba-3 tools as follows:
&rootprompt; pdbedit -L
root:0:root
nobody:65534:nobody
bobj:1000:System User
stans:1001:System User
chrisr:1002:System User
maryv:1003:System User
bldg1$:1006:bldg1$
&rootprompt; net groupmap list
Domain Admins (S-1-5-21-3504140859-...-2431957765-512) -> Domain Admins
Domain Users (S-1-5-21-3504140859-...-2431957765-513) -> Domain Users
Domain Guests (S-1-5-21-3504140859-...-2431957765-514) -> Domain Guests
Administrators (S-1-5-21-3504140859-...-2431957765-544) -> Administrators
...
Accounts (S-1-5-21-3504140859-1010554828-2431957765-3001) -> Accounts
Finances (S-1-5-21-3504140859-1010554828-2431957765-3003) -> Finances
PIOps (S-1-5-21-3504140859-1010554828-2431957765-3005) -> PIOps
The above results show that all things are in order.
The server you have so carefully built is now ready for another important step. Now
start the Samba-3 server and validate its operation. Execute the following to render all
the processes needed fully operative so that, upon system reboot, they are automatically
started:
&rootprompt; chkconfig named on
&rootprompt; chkconfig dhcpd on
&rootprompt; chkconfig nmb on
&rootprompt; chkconfig smb on
&rootprompt; chkconfig winbind on
&rootprompt; rcnmb start
&rootprompt; rcsmb start
&rootprompt; rcwinbind start
Samba-3 should now be running and is ready for a quick test. But not quite yet!
Your new BLDG1, BLDG2 servers do not have home directories for users.
To rectify this using the SUSE yast2 utility or by manually editing the /etc/fstab
file, add a mount entry to mount the home directory that has been exported
from the MASSIVE server. Mount this resource before proceeding. An alternate
approach could be to create local home directories for users who are to use these machines.
This is a choice that you, as system administrator, must make. The following entry in the
/etc/fstab file suffices for now:
massive.abmas.biz:/home /home nfs rw 0 0
To mount this resource, execute:
&rootprompt; mount -a
Verify that the home directory has been mounted as follows:
&rootprompt; df | grep home
massive:/home 29532988 283388 29249600 1% /home
Implement a quick check using one of the users that is in the LDAP database. Here you go:
&rootprompt; smbclient //bldg1/bobj -Ubobj%n3v3r2l8
smb: \> dir
. D 0 Wed Dec 17 01:16:19 2003
.. D 0 Wed Dec 17 19:04:42 2003
bin D 0 Tue Sep 2 04:00:57 2003
Documents D 0 Sun Nov 30 07:28:20 2003
public_html D 0 Sun Nov 30 07:28:20 2003
.urlview H 311 Fri Jul 7 06:55:35 2000
.dvipsrc H 208 Fri Nov 17 11:22:02 1995
57681 blocks of size 524288. 57128 blocks available
smb: \> q
Configuration of BDC Called: <constant>BLDG2</constant>
Install the files in ,
, and
into the /etc/samba/ directory. The three files
should be added together to form the &smb.conf; file.
Follow carefully the steps shown in , starting at step 2.
LDAP Based &smb.conf; File, Server: BLDG1Global parametersLOCALEMEGANET2BLDG1ldapsam:ldap://massive.abmas.bizYes/etc/samba/smbusers10/var/log/samba/%m50139 445wins bcast hostsCUPSNoscripts\logon.bat\\%L\profiles\%UX:YesNo172.16.0.1dc=abmas,dc=bizou=Peopleou=Peopleou=Groupsou=Idmapcn=Manager,dc=abmas,dc=bizldap:ldap://massive.abmas.biz10000-2000010000-20000cupsroot, chrisrLDAP Based &smb.conf; File, Server: BLDG2Global parametersLOCALEMEGANET2BLDG2ldapsam:ldap://massive.abmas.bizYes/etc/samba/smbusers10/var/log/samba/%m50139 445wins bcast hostsCUPSNoscripts\logon.bat\\%L\profiles\%UX:YesNo172.16.0.1dc=abmas,dc=bizou=Peopleou=Peopleou=Groupsou=Idmapcn=Manager,dc=abmas,dc=bizldap:ldap://massive.abmas.biz10000-2000010000-20000cupsroot, chrisrLDAP Based &smb.conf; File, Shares Section &smbmdash; Part AAccounting Files/data/accountsNoFinancial Services Files/data/serviceNoProperty Insurance Files/data/pidataNoHome Directories%SNoNoSMB Print Spool/var/spool/sambaYesYesNoLDAP Based &smb.conf; File, Shares Section &smbmdash; Part BApplication Files/appsbjordanNoNetwork Logon Service/var/lib/samba/netlogonYesNoProfile Share/var/lib/samba/profilesNoYesProfile Data Share/var/lib/samba/profdataNoYesPrinter Drivers/var/lib/samba/driversyesnoyesroot, chrisrLDIF IDMAP Add-On Load File &smbmdash; File: /etc/openldap/idmap.LDIF
dn: ou=Idmap,dc=abmas,dc=biz
objectClass: organizationalUnit
ou: idmap
structuralObjectClass: organizationalUnit
Miscellaneous Server Preparation Tasks
My father would say, Dinner is not over until the dishes have been done.
The makings of a great network environment take a lot of effort and attention to detail.
So far you have completed most of the complex (and to many administrators, the interesting
part of server configuration) steps, but remember to tie it all together. Here are
a few more steps that must be completed so that your network runs like a well-rehearsed
orchestra.
Configuring Directory Share Point Roots
In your &smb.conf; file, you have specified Windows shares. Each has a
path
parameter. Even though it is obvious to all, one of the common Samba networking problems is
caused by forgetting to verify that every such share root directory actually exists and that it
has the necessary permissions and ownership.
Here is an example, but remember to create the directory needed for every share:
&rootprompt; mkdir -p /data/{accounts,finsvcs,piops}
&rootprompt; mkdir -p /apps
&rootprompt; chown -R root.root /data
&rootprompt; chown -R root.root /apps
&rootprompt; chown -R bobj.Accounts /data/accounts
&rootprompt; chown -R bobj.Finances /data/finsvcs
&rootprompt; chown -R bobj.PIOps /data/pidata
&rootprompt; chmod -R ug+rwxs,o-rwx /data
&rootprompt; chmod -R ug+rwx,o+rx-w /apps
Configuring Profile Directories
You made a conscious decision to do everything it would take to improve network client
performance. One of your decisions was to implement folder redirection. This means that Windows
user desktop profiles are now made up of two components &smbmdash; a dynamically loaded part and a set of file
network folders.
For this arrangement to work, every user needs a directory structure for the network folder
portion of their profile as shown here:
&rootprompt; mkdir -p /var/lib/samba/profdata
&rootprompt; chown root.root /var/lib/samba/profdata
&rootprompt; chmod 755 /var/lib/samba/profdata
# Per user structure
&rootprompt; cd /var/lib/samba/profdata
&rootprompt; mkdir -p username
&rootprompt; for i in InternetFiles Cookies History AppData \
LocalSettings MyPictures MyDocuments Recent
&rootprompt; do
&rootprompt; mkdir username/$i
&rootprompt; done
&rootprompt; chown -R username.Domain\ Users username
&rootprompt; chmod -R 750 usernameroaming profilemandatory profile
You have three options insofar as the dynamically loaded portion of the roaming profile
is concerned:
You may permit the user to obtain a default profile.You can create a mandatory profile.You can create a group profile (which is almost always a mandatory profile).
Mandatory profiles cannot be overwritten by a user. The change from
a user profile to a mandatory profile is effected by renaming the
NTUSER.DAT to
NTUSER.MAN, i.e., just by changing the filename
extension.
SRVTOOLS.EXEDomain User Manager
The location of the profile that a user can obtain is set in the users' account in the LDAP passdb backend.
You can manage this using the Idealx smbldap-tools or using the
Windows NT4 Domain User Manager.
It may not be obvious that you must ensure that the root directory for the user's profile exists
and has the needed permissions. Use the following commands to create this directory:
&rootprompt; mkdir -p /var/lib/samba/profiles/username
&rootprompt; chown username.Domain\ Users
/var/lib/samba/profiles/username
&rootprompt; chmod 700 /var/lib/samba/profiles/usernamePreparation of Logon Scriptslogon script
The use of a logon script with Windows XP Professional is an option that every site should consider.
Unless you have locked down the desktop so the user cannot change anything, there is risk that
a vital network drive setting may be broken or that printer connections may be lost. Logon scripts
can help to restore persistent network folder (drive) and printer connections in a predictable
manner. One situation in which such breakage may occur in particular is when a mobile PC (notebook)
user attaches to another company's network that forces environment changes that are alien to your
network.
If you decide to use network logon scripts, by reference to the &smb.conf; files for the Domain
Controllers, you see that the path to the share point for the
NETLOGON
share defined is /var/lib/samba/netlogon. The path defined for the logon
script inside that share is scripts\logon.bat. This means that as a Windows
NT/200x/XP client logs onto the network, it tries to obtain the file
logon.bat
from the fully qualified path /var/lib/samba/netlogon/scripts. This fully
qualified path should, therefore, exist where you install the logon.bat.
You can, of course, create the fully qualified path by executing:
&rootprompt; mkdir -p /var/lib/samba/netlogon/scripts
You should research the options for logon script implementation by referring to TOSHARG, Chapter 21,
Section 21.4. A quick Web search will bring up a host of options. One of the most popular logon
facilities in use today is called KiXtart.Assigning User Rights and Privileges
The ability to perform tasks such as joining Windows clients to the domain can be assigned to
normal user accounts. By default, only the domain administrator account (root on UNIX
systems because it has UID=0) can add accounts. New to Samba 3.0.11 is the ability to grant
this privilege in a very limited fashion to particular accounts.
By default, even Samba 3.0.11 does not grant any rights even to the Domain Admins
group. Here we will grant this group all privileges. The assignment of user rights and privileges
requires that the parameter enable privileges = Yes must be set in the &smb.conf; file.
Samba limits privileges on a per-server basis. This is a deliberate limitation so that users who
are granted rights can be restricted to particular machines. It is left to the network administrator
to determine which rights should be provided and to whom.
Setting up User Privileges
Log onto the primary domain controller (PDC) as the root account.
Execute the following command to grant the Domain Admins group all
rights and privileges:
&rootprompt; net -S MASSIVE -U root%not24get rpc rights grant \
"MEGANET2\Domain Admins" SeMachineAccountPrivilege \
SePrintOperatorPrivilege SeAddUsersPrivilege \
SeDiskOperatorPrivilege SeRemoteShutdownPrivilege
Successfully granted rights.
Repeat this step on each domain controller in each case substituting the name of the server
(e.g.: BLDG1, BLDG2) in place of the PDC called MASSIVE.
In this step the privilege will be granted to Bob Jordan (bobj) to add Windows workstations
to the domain. Execute the following only on the PDC. It is not necessary to do this on
BDCs or on DMS machines because machine accounts are only ever added by the PDC:
&rootprompt; net -S MASSIVE -U root%not24get rpc rights grant \
"MEGANET2\bobj" SeMachineAccountPrivilege
Successfully granted rights.
Verify that the assignment of privileges have been correctly applied by executing:
net rpc rights list accounts -Uroot%not24get
MEGANET2\bobj
SeMachineAccountPrivilege
S-0-0
No privileges assigned
BUILTIN\Print Operators
No privileges assigned
BUILTIN\Account Operators
No privileges assigned
BUILTIN\Backup Operators
No privileges assigned
BUILTIN\Server Operators
No privileges assigned
BUILTIN\Administrators
No privileges assigned
Everyone
No privileges assigned
MEGANET2\Domain Admins
SeMachineAccountPrivilege
SePrintOperatorPrivilege
SeAddUsersPrivilege
SeRemoteShutdownPrivilege
SeDiskOperatorPrivilege
Windows Client ConfigurationNETLOGON
In the next few sections, you can configure a new Windows XP Professional disk image on a staging
machine. You will configure all software, printer settings, profile and policy handling, and desktop
default profile settings on this system. When it is complete, you copy the contents of the
C:\Documents and Settings\Default User directory to a directory with the same
name in the NETLOGON share on the Domain Controllers.
Much can be learned from the Microsoft Support site regarding how best to set up shared profiles.
One knowledge-base article in particular stands out. See:
How to Create a
Base Profile for All Users.Configuration of Default Profile with Folder Redirectionfolder redirection
Log onto the Windows XP Professional workstation as the local Administrator.
It is necessary to expose folders that are generally hidden to provide
access to the Default User
folder.
Expose Hidden Folders
Launch the Windows Explorer by clicking
StartMy ComputerToolsFolder OptionsView Tab.
Select Show hidden files and folders,
and click OK. Exit Windows Explorer.
regedt32
Launch the Registry Editor. Click
StartRun. Key in regedt32, and click
OK.
Redirect Folders in Default System User ProfileHKEY_LOCAL_MACHINEDefault User
Give focus to HKEY_LOCAL_MACHINE hive entry in the left panel.
Click FileLoad Hive...[Panel] Documents and Settings[Panel] Default UserNTUSEROpen. In the dialog box that opens, enter the
key name Default and click OK.
Browse inside the newly loaded Default folder to:
HKEY_LOCAL_MACHINE\Default\Software\Microsoft\Windows\
CurrentVersion\Explorer\User Shell Folders\
The contents of the right panel reveals the contents as
shown in .
%USERPROFILE%%LOGONSERVER%
You edit hive keys. Acceptable values to replace the
%USERPROFILE% variable includes:
A drive letter such as: U:A direct network path such as:
\\MASSIVE\profdataA network redirection (UNC name) that contains a macro such as: %LOGONSERVER%\profdata\registry keys
Set the registry keys as shown in . Your implementation makes the assumption
that users have statically located machines. Notebook computers (mobile users) need to be
accommodated using local profiles. This is not an uncommon assumption.
Click back to the root of the loaded hive Default.
Click FileUnload Hive...Yes.
Registry Editor
Click FileExit. This exits the
Registry Editor.
Now follow the procedure given in . Make sure that each folder you
have redirected is in the exclusion list.
You are now ready to copy
There is an alternate method by which a Default User profile can be added to the
NETLOGON share. This facility in the Windows System tool
permits profiles to be exported. The export target may be a particular user or
group profile share point, or else into the NETLOGON share.
In this case, the profile directory must be named
Default User.
the Default User profile to the Samba Domain Controllers. Launch Microsoft
Windows Explorer, and use it to copy the full contents of the
directory Default User
that is in the C:\Documents and Settings to the root directory of the
NETLOGON share. If the NETLOGON share has the defined
UNIX path of /var/lib/samba/netlogon, when the copy is complete there must be
a directory in there called Default User.
Reset Folder Display to Original Behavior
To launch the Windows Explorer, click
StartMy ComputerToolsFolder OptionsView Tab.
Deselect Show hidden files and folders,
and click OK.
Exit Windows Explorer.
Windows XP Professional &smbmdash; User Shared FoldersXP-screen001
Configuration of MS Outlook to Relocate PST FileOutlookPST
Microsoft Outlook can store a Personal Storage file, generally known as a PST file.
It is the nature of email storage that this file grows, at times quite rapidly.
So that users' email is available to them at every workstation they may log onto,
it is common practice in well-controlled sites to redirect the PST folder to the
users' home directory. Follow these steps for each user who wishes to do this.
It is presumed that Outlook Express has been configured for use.
Launch Outlook Express 6. Click
ToolsOptionsMaintenanceStore FolderChange.
Follow the on-screen prompts to relocate the PST file to the desired location.
Configure Delete Cached Profiles on Logout
To configure the Windows XP Professional client to auto-delete roaming profiles on logout:
MMC
Click
StartRun. In the dialog box, enter: MMC
and click OK.
Follow these steps to set the default behavior of the staging machine so that all roaming
profiles are deleted as network users log out of the system. Click
FileAdd/Remove Snap-inAddGroup PolicyAddFinishCloseOK.
Microsoft Management ConsoleMMC
The Microsoft Management Console now shows the Group Policy
utility that enables you to set the policies needed. In the left panel, click
Local Computer PolicyAdministrative TemplatesSystemUser Profiles. In the right panel, set the properties shown here by double-clicking on each
item as shown:
Do not check for user ownership of Roaming Profile Folders = EnabledDelete cached copies of roaming profiles = Enabled
Close the Microsoft Management Console. The settings take immediate effect and persist onto all image copies
made of this system to deploy the new standard desktop system.
Uploading Printer Drivers to Samba Serversprintingdrag-and-drop
Users want to be able to use network printers. You have a vested interest in making
it easy for them to print. You have chosen to install the printer drivers onto the Samba
servers and to enable point-and-click (drag-and-drop) printing. This process results in
Samba being able to automatically provide the Windows client with the driver necessary to
print to the printer chosen. The following procedure must be followed for every network
printer:
Uploading Printer Drivers
Join your Windows XP Professional workstation (the staging machine) to the
MEGANET2 Domain. If you are not sure of the procedure,
follow the guidance given in .
After the machine has re-booted, log onto the workstation as the domain
root (this is the Administrator account for the
operating system that is the host platform for this implementation of Samba.
Launch MS Windows Explorer. Navigate in the left panel. Click
My Network PlacesEntire NetworkMicrosoft Windows NetworkMeganet2Massive. Click on MassivePrinters and Faxes.
Identify a printer that is shown in the right panel. Let us assume the printer is called
ps01-color. Right-click on the ps01-color icon
and select the Properties entry. This opens a dialog box that indicates
that The printer driver is not installed on this computer. Some printer properties
will not be accessible unless you install the printer driver. Do you want to install the
driver now? It is important at this point you answer No.
The printer properties panel for the ps01-color printer on the server
MASSIVE is displayed. Click the Advanced tab.
Note that the box labeled Driver is empty. Click the New Driver
button that is next to the Driver box. This launches the quoteAdd Printer Wizard.
Add Printer WizardAPWAPW
The Add Printer Driver Wizard on MASSIVE panel
is now presented. Click Next to continue. From the left panel, select the
Printer Manufacturer. In your case, you are adding a driver for a printer manufactured by
Lexmark. In the right panel, select the printer (Lexmark Optra Color 40 PS). Click
Next, and then Finish to commence driver upload. A
progress bar appears and instructs you as each file is being uploaded and that it is being
directed at the network server \\massive\ps01-color.
printersAdvancedprintersPropertiesprintersSharingprintersGeneralprintersSecurityAD printer publishing
The driver upload completes in anywhere from a few seconds to a few minutes. When it completes,
you are returned to the Advanced tab in the Properties panel.
You can set the Location (under the General tab), and Security settings (under
the Security tab). Under the Sharing tab it is possible to
load additional printer drivers, there is also a check-box in this tab called List in the
directory. When this box is checked the printer will be published in Active Directory
(Applicable to Active Directory use only.)
printersDefault Settings
Click OK. It will take a minute or so to upload the settings to the server.
You are now returned to the Printers and Faxes on Massive monitor.
Right-click on the printer, click PropertiesDevice Settings. Now change the settings to suit
your requirements. BE CERTAIN TO CHANGE AT LEAST ONE SETTING and apply the changes even if
you need to reverse them changes back to their original settings.
This is necessary so that the printer settings are initialized in the Samba printers
database. Click Apply to commit your settings. Revert any settings you changed
just to initialize the Samba printers database entry for this printer. If you need to revert a setting,
Click Apply again.
Print Test Page
Verify that all printer settings are at the desired configuration. When you are satisfied that they are,
click the General tab. Now click the Print Test Page button.
A test page should print. Verify that it has printed correctly. Then click OK
in the panel that is newly presented. Click OK on the ps01-color on
massive Properties panel.
You must repeat this process for all network printers (i.e., for every printer, on each server).
When you have finished uploading drivers to all printers, close all applications. The next task
is to install software your users require to do their work.
Software Installation
Your network has both fixed desktop workstations as well as notebook computers. As a general rule, it is
a good idea to not tamper with the operating system that is provided by the notebook computer manufacturer.
Notebooks require special handling that is beyond the scope of this chapter.
For desktop systems, the installation of software onto administratively centralized application servers
make a lot of sense. This means that you can manage software maintenance from a central
perspective and that only minimal application stub-ware needs to be installed onto the desktop
systems. You should proceed with software installation and default configuration as far as is humanly
possible and so long as it makes sense to do so. Make certain to thoroughly test and validate every aspect
of software operations and configuration.
When you believe that the overall configuration is complete, be sure to create a shared group profile
and migrate that to the Samba server for later re-use when creating custom mandatory profiles, just in
case a user may have specific needs you had not anticipated.
Roll-out Image Creation
The final steps before preparing the distribution Norton Ghost image file you might follow are:
Un-join the domain &smbmdash; Each workstation requires a unique name and must be independently
joined into Domain Membership.
De-fragment the hard disk &smbmdash; While not obvious to the uninitiated, de-fragmentation results
in better performance and often significantly reduces the size of the compressed disk image. That
also means it will take less time to deploy the image onto 500 workstations.
Key Points Learned
This chapter has introduced many new concepts. Is it a sad fact that the example presented deliberately
avoided any consideration of security. Security does not just happen; you must design it into your total
network. Security begins with a systems design and implementation that anticipates hostile behavior from
users both inside and outside the organization. Hostile and malicious intruders do not respect barriers;
they accept them as challenges. For that reason, if not simply from a desire to establish safe networking
practices, you must not deploy the design presented in this book in an environment where there is risk
of compromise.
Access Control ListsACLsACLs
As a minimum, the LDAP server must be protected by way of Access Control Lists (ACLs) and it must be
configured to use secure protocols for all communications over the network. Of course, secure networking
does not result just from systems design and implementation but involves constant user education
training, and above all disciplined attention to detail and constant searching for signs of unfriendly
or alien activities. Security is itself a topic for a whole book. Please do consult appropriate sources.
Jerry Carter's book LDAP System
Administration is a good place to start reading about OpenLDAP as well as security considerations.
The substance of this chapter that has been deserving of particular attention includes:
Implementation of an OpenLDAP-based passwd backend &smbmdash; necessary to support distributed
Domain Control.
Implementation of Samba Primary and Secondary Domain Controllers with a common LDAP backend
for user and group accounts that is shared with the UNIX system through the PADL nss_ldap and
pam_ldap tool-sets.
Use of the Idealx smbldap-tools scripts for UNIX (Posix) account management as well as
to manage Samba Windows user and group accounts.
The basics of implementation of Group Policy controls for Windows network clients.
Control over roaming profiles, with particular focus on folder redirection to network drives.
Use of the CUPS printing system together with Samba-based printer driver auto-download.
Questions and Answers
Well, here we are at the end of this chapter and we have only ten questions to help you to
remember so much. There are bound to be some sticky issues here.
Why did you not cover secure practices? Isn't it rather irresponsible to instruct
network administrators to implement insecure solutions?
Let's get this right. This is a book about Samba, not about OpenLDAP and secure
communication protocols for subjects other than Samba. Earlier on, you note
that the Dynamic DNS and DHCP solutions also used no protective secure communications
protocols. The reason for this is simple: There are so many ways of implementing
secure protocols that this book would have been even larger and more complex.
The solutions presented here all work (at least they did for me). Network administrators
have the interest and the need to be better trained and instructed in secure networking
practices and ought to implement safe systems. I made the decision, right or wrong,
to keep this material as simple as possible. The intent of this book is to demonstrate
a working solution and not to discuss too many peripheral issues.
This book makes little mention of backup techniques. Does that mean that I am recommending
that you should implement a network without provision for data recovery and for disaster
management? Back to our focus: The deployment of Samba has been clearly demonstrated.
You have focused much on SUSE Linux and little on the market leader, Red Hat. Do
you have a problem with Red Hat Linux? Doesn't that make your guidance irrelevant
to the Linux I might be using?
Both Red Hat Linux and SUSE Linux comply with the Linux Standards Base specifications
for a standard Linux distribution. The differences are marginal. Surely you know
your Linux platform and you do have access to administration manuals for it. This
book is not a Linux tutorial; it is a Samba tutorial. Let's keep the focus on
the Samba part of the book; all the other bits are peripheral (but important) to
creation of a total network solution.
What I find interesting is the attention reviewers give to Linux installation and to
the look and feel of the desktop, but does that make for a great server? In this book,
I have paid particular attention to the details of creating a whole solution framework.
I have not tightened every nut and bolt, but I have touched on all the issues you
need to be familiar with. Over the years many people have approached me wanting to
know the details of exactly how to implement a DHCP and Dynamic DNS server with Samba
and WINS. In this chapter, it is plain to see what needs to be configured to provide
transparent interoperability. Likewise for CUPS and Samba inter-operation. These are
key stumbling areas for many people.
At every critical junction, I have provided comparative guidance for both SUSE and
Red Hat Linux. Both manufacturers have done a great job in furthering the cause
of open source software. I favor neither and respect both. I like particular
features of both products (companies also). No bias in presentation is intended.
Oh, before I forget, I particularly like Debian Linux; that is my favorite playground.
You did not use SWAT to configure Samba. Is there something wrong with it?
That is a good question. As it is, the &smb.conf; file configurations are presented
in as direct a format as possible. Adding SWAT into the equation would have complicated
matters. I sought simplicity of implementation. The fact is that I did use SWAT to
create the files in the first place.
There are people in the Linux and open source community who feel that SWAT is dangerous
and insecure. Many will not touch it with a barge-pole. By not introducing SWAT, I
hope to have brought their interests on board. SWAT is well covered is TOSHARG.
You have exposed a well-used password not24get. Is that
not irresponsible?
Well, I had to use a password of some sort. At least this one has been consistently
used throughout. I guess you can figure out that in a real deployment it would make
sense to use a more secure and original password.
The Idealx smbldap-tools create many domain group accounts that are not used. Is that
a good thing?
I took this up with Idealx and found them most willing to change that in the next version.
Let's give Idealx some credit for the contribution they have made. I appreciate their work
and, besides, it does no harm to create accounts that are not now used as at some time
Samba may well use them.
Can I use LDAP just for Samba accounts and not for UNIX system accounts?
Yes, you can do that for user accounts only. Samba requires there to be a Posix (UNIX)
group account for every Windows Domain group account. But if you put your users into
the system password account, how do you plan to keep all domain controller system
password files in sync? I think that having everything in LDAP makes a lot of sense
for the UNIX admin who is still learning the craft and is migrating from MS Windows.
Why are the Windows Domain RID portions not the same as the UNIX UID?
Samba uses a well-known public algorithm for assigning RIDs from UIDs and GIDs.
This algorithm ought to ensure that there will be no clashes with well-known RIDs.
Well-known RIDs have special significance to MS Windows clients. The automatic
assignment used the calculation: RID = UID x 2 + 1000. Of course, Samba does
permit you to override that to some extent. See the &smb.conf; man page entry
for algorithmic rid base.
Printer configuration examples all show printing to the HP port 9100. Does this
mean that I must have HP printers for these solutions to work?
No. You can use any type of printer and must use the interfacing protocol supported
by the printer. Many networks use LPR/LPD print servers to which are attached
PCL printers, InkJet printers, plotters, and so on. At home I use a USB attached
Inkjet printer. Use the appropriate device URI (Universal Resource Interface)
argument to the lpadmin -v option that is right for your
printer.
Is folder redirection dangerous? I've heard that you can lose your data that way.
The only loss of data I know of that involved folder redirection was caused by
manual misuse of the redirection tool. The administrator redirected a folder to
a network drive and said he wanted to migrate (move) the data over. Then he
changed his mind, so he moved the folder back to the roaming profile. This time,
he declined to move the data because he thought it was still in the local profile
folder. That was not the case, so by declining to move the data back, he wiped out
the data. You cannot hold the tool responsible for that. Caveat emptor still applies.
Is it really necessary to set a local Group Policy to exclude the redirected
folders from the roaming profile?
Yes. If you do not do this, the data will still be copied from the network folder
(share) to the local cached copy of the profile.