&author.jht;
Stand-Alone Servers
Stand-Alone servers are independant of Domain Controllers on the network.
They are NOT domain members and function more like workgroup servers. In many
cases a stand-alone server is configured with a minimum of security control
with the intent that all data served will be readilly accessible to all users.
Features and Benefits
Stand-Alone servers can be as secure or as insecure as needs dictate. They can
have simple or complex configurations. Above all, despite the hoopla about
Domain security they remain a very common installation.
If all that is needed is a server for read-only files, or for
printers alone, it may not make sense to affect a complex installation.
For example: A drafting office needs to store old drawings and reference
standards. No-one can write files to the server as it is legislatively
important that all documents remain unaltered. A share mode read-only stand-alone
server is an ideal solution.
Another situation that warrants simplicity is an office that has many printers
that are queued off a single central server. Everyone needs to be able to print
to the printers, there is no need to affect any access controls and no files will
be served from the print server. Again a share mode stand-alone server makes
a great solution.
Background
The term stand-alone server means that the server
will provide local authentication and access control for all resources
that are available from it. In general this means that there will be a
local user database. In more technical terms, it means that resources
on the machine will be made available in either SHARE mode or in
USER mode.
No special action is needed other than to create user accounts. Stand-alone
servers do NOT provide network logon services. This means that machines that
use this server do NOT perform a domain log onto it. Whatever logon facility
the workstations are subject to is independant of this machine. It is however
necessary to accomodate any network user so that the logon name they use will
be translated (mapped) locally on the stand-alone server to a locally known
user name. There are several ways this cane be done.
Samba tends to blur the distinction a little in respect of what is
a stand-alone server. This is because the authentication database may be
local or on a remote server, even if from the samba protocol perspective
the samba server is NOT a member of a domain security context.
Through the use of PAM (Pluggable Authentication Modules) and nsswitch
(the name service switcher) the source of authentication may reside on
another server. We call this the authentication server. This means that
the samba server may use the local Unix/Linux system password database
(/etc/passwd or /etc/shadow), may use a local smbpasswd file, or may use
an LDAP back end, or even via PAM and Winbind another CIFS/SMB server
for authentication.
Example Configuration
The following examples are designed to inspire simplicity. It is too easy to
attempt a high level of creativity and to introduce too much complexity in
server and network design.
Reference Documentation Server
Configuration of a read-only data server that EVERYONE can access is very simple.
Here is the smb.conf file that will do this. Assume that all the reference documents
are stored in the directory /export, that the documents are owned by a user other than
nobody. No home directories are shared, that are no users in the /etc/passwd
Unix system database. This is a very simple system to administer.
Share Mode Read Only Stand-Alone Server
# Global parameters
[global]
workgroup = MYGROUP
netbios name = REFDOCS
security = SHARE
passdb backend = guest
wins server = 192.168.1.1
[data]
comment = Data
path = /export
guest only = Yes
In the above example the machine name is set to REFDOCS, the workgroup is set to the name
of the local workgroup so that the machine will appear in with systems users are familiar
with. The only password backend required is the "guest" backend so as to allow default
unprivilidged account names to be used. Given that there is a WINS server on this network
we do use it.
Central Print Serving
Configuration of a simple print server is very simple if you have all the right tools
on your system.
Assumptions:
The print server must require no administration
The print spooling and processing system on our print server will be CUPS.
(Please refer to the chapter on printing for more information).
All printers will that the print server will service will be network
printers. They will be correctly configured, by the administrator,
in the CUPS environment.
All workstations will be installed using postscript drivers. The printer
of choice is the Apple Color LaserWriter.
In this example our print server will spool all incoming print jobs to
/var/spool/samba until the job is ready to be submitted by
samba to the CUPS print processor. Since all incoming connections will be as
the anonymous (guest) user two things will be required:
Enablement for Anonymous Printing
The Unix/Linux system must have a guest account.
The default for this is usually the account nobody.
To find the correct name to use for your version of Samba do the
following:
testparm -s -v | grep "guest account"
Then make sure that this account exists in your system password
database (/etc/passwd).
The directory into which Samba will spool the file must have write
access for the guest account. The following commands will ensure that
this directory is available for use:
mkdir /var/spool/samba
chown nobody.nobody /var/spool/samba
chmod a+rwt /var/spool/samba
Simple Central Print Server
# Global parameters
[global]
workgroup = MYGROUP
netbios name = PTRSVR1
security = SHARE
passdb backend = guest
wins server = 192.168.1.1
[printers]
comment = All Printers
path = /var/spool/samba
printer admin = root
guest ok = Yes
printable = Yes
printing = cups
use client driver = Yes
browseable = No
Common Errors
The greatest mistake so often made is to make a network configuration too complex.
It pays to use the simplest solution that will meet the needs of the moment.