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diff --git a/docs/docbook/projdoc/Browsing.sgml b/docs/docbook/projdoc/Browsing.sgml deleted file mode 100644 index ca2f6dc57b..0000000000 --- a/docs/docbook/projdoc/Browsing.sgml +++ /dev/null @@ -1,807 +0,0 @@ -<chapter id="improved-browsing"> -<chapterinfo> - <author> - <affiliation> - <orgname>Samba Team</orgname> - </affiliation> - </author> - - <pubdate> (5 July 1998) </pubdate> -</chapterinfo> - -<title>Improved browsing in samba</title> - -<sect1> -<title>Overview of browsing</title> - -<para> -SMB networking provides a mechanism by which clients can access a list -of machines in a network, a so-called <command>browse list</command>. This list -contains machines that are ready to offer file and/or print services -to other machines within the network. Thus it does not include -machines which aren't currently able to do server tasks. The browse -list is heavily used by all SMB clients. Configuration of SMB -browsing has been problematic for some Samba users, hence this -document. -</para> - -<para> -MS Windows 2000 and later, as with Samba 3 and later, can be -configured to not use NetBIOS over TCP/IP. When configured this way -it is imperative that name resolution (using DNS/LDAP/ADS) be correctly -configured and operative. Browsing will NOT work if name resolution -from SMB machine names to IP addresses does not function correctly. -</para> - -<para> -Where NetBIOS over TCP/IP is enabled use of a WINS server is highly -recommended to aid the resolution of NetBIOS (SMB) names to IP addresses. -WINS allows remote segment clients to obtain NetBIOS name_type information -that can NOT be provided by any other means of name resolution. -</para> - -</sect1> - -<sect1> -<title>Browsing support in samba</title> - -<para> -Samba facilitates browsing. The browsing is supported by &nmbd; -and is also controlled by options in the &smb.conf; file. -Samba can act as a local browse master for a workgroup and the ability -for samba to support domain logons and scripts is now available. -</para> - -<para> -Samba can also act as a domain master browser for a workgroup. This -means that it will collate lists from local browse masters into a -wide area network server list. In order for browse clients to -resolve the names they may find in this list, it is recommended that -both samba and your clients use a WINS server. -</para> - -<para> -Note that you should NOT set Samba to be the domain master for a -workgroup that has the same name as an NT Domain: on each wide area -network, you must only ever have one domain master browser per workgroup, -regardless of whether it is NT, Samba or any other type of domain master -that is providing this service. -</para> - -<note><para> -Nmbd can be configured as a WINS server, but it is not -necessary to specifically use samba as your WINS server. MS Windows -NT4, Server or Advanced Server 2000 or 2003 can be configured as -your WINS server. In a mixed NT/2000/2003 server and samba environment on -a Wide Area Network, it is recommended that you use the Microsoft -WINS server capabilities. In a samba-only environment, it is -recommended that you use one and only one Samba server as your WINS server. -</para></note> - -<para> -To get browsing to work you need to run nmbd as usual, but will need -to use the <command>workgroup</command> option in &smb.conf; -to control what workgroup Samba becomes a part of. -</para> - -<para> -Samba also has a useful option for a Samba server to offer itself for -browsing on another subnet. It is recommended that this option is only -used for 'unusual' purposes: announcements over the internet, for -example. See <command>remote announce</command> in the -&smb.conf; man page. -</para> -</sect1> - -<sect1> -<title>Problem resolution</title> - -<para> -If something doesn't work then hopefully the log.nmb file will help -you track down the problem. Try a debug level of 2 or 3 for finding -problems. Also note that the current browse list usually gets stored -in text form in a file called <filename>browse.dat</filename>. -</para> - -<para> -Note that if it doesn't work for you, then you should still be able to -type the server name as <filename>\\SERVER</filename> in filemanager then -hit enter and filemanager should display the list of available shares. -</para> - -<para> -Some people find browsing fails because they don't have the global -<command>guest account</command> set to a valid account. Remember that the -IPC$ connection that lists the shares is done as guest, and thus you must -have a valid guest account. -</para> - -<para><emphasis> -MS Windows 2000 and upwards (as with Samba) can be configured to disallow -anonymous (ie: Guest account) access to the IPC$ share. In that case, the -MS Windows 2000/XP/2003 machine acting as an SMB/CIFS client will use the -name of the currently logged in user to query the IPC$ share. MS Windows -9X clients are not able to do this and thus will NOT be able to browse -server resources. -</emphasis></para> - -<para> -The other big problem people have is that their broadcast address, -netmask or IP address is wrong (specified with the "interfaces" option -in &smb.conf;) -</para> -</sect1> - -<sect1> -<title>Browsing across subnets</title> -<para> -Since the release of Samba 1.9.17(alpha1) Samba has been -updated to enable it to support the replication of browse lists -across subnet boundaries. New code and options have been added to -achieve this. This section describes how to set this feature up -in different settings. -</para> - -<para> -To see browse lists that span TCP/IP subnets (ie. networks separated -by routers that don't pass broadcast traffic) you must set up at least -one WINS server. The WINS server acts as a DNS for NetBIOS names, allowing -NetBIOS name to IP address translation to be done by doing a direct -query of the WINS server. This is done via a directed UDP packet on -port 137 to the WINS server machine. The reason for a WINS server is -that by default, all NetBIOS name to IP address translation is done -by broadcasts from the querying machine. This means that machines -on one subnet will not be able to resolve the names of machines on -another subnet without using a WINS server. -</para> - -<para> -Remember, for browsing across subnets to work correctly, all machines, -be they Windows 95, Windows NT, or Samba servers must have the IP address -of a WINS server given to them by a DHCP server, or by manual configuration -(for Win95 and WinNT, this is in the TCP/IP Properties, under Network -settings) for Samba this is in the &smb.conf; file. -</para> - -<sect2> -<title>How does cross subnet browsing work ?</title> - -<para> -Cross subnet browsing is a complicated dance, containing multiple -moving parts. It has taken Microsoft several years to get the code -that achieves this correct, and Samba lags behind in some areas. -Samba is capable of cross subnet browsing when configured correctly. -</para> - -<para> -Consider a network set up as follows : -</para> - -<para> -<programlisting> - (DMB) - N1_A N1_B N1_C N1_D N1_E - | | | | | - ------------------------------------------------------- - | subnet 1 | - +---+ +---+ - |R1 | Router 1 Router 2 |R2 | - +---+ +---+ - | | - | subnet 2 subnet 3 | - -------------------------- ------------------------------------ - | | | | | | | | - N2_A N2_B N2_C N2_D N3_A N3_B N3_C N3_D - (WINS) -</programlisting> -</para> - -<para> -Consisting of 3 subnets (1, 2, 3) connected by two routers -(R1, R2) - these do not pass broadcasts. Subnet 1 has 5 machines -on it, subnet 2 has 4 machines, subnet 3 has 4 machines. Assume -for the moment that all these machines are configured to be in the -same workgroup (for simplicities sake). Machine N1_C on subnet 1 -is configured as Domain Master Browser (ie. it will collate the -browse lists for the workgroup). Machine N2_D is configured as -WINS server and all the other machines are configured to register -their NetBIOS names with it. -</para> - -<para> -As all these machines are booted up, elections for master browsers -will take place on each of the three subnets. Assume that machine -N1_C wins on subnet 1, N2_B wins on subnet 2, and N3_D wins on -subnet 3 - these machines are known as local master browsers for -their particular subnet. N1_C has an advantage in winning as the -local master browser on subnet 1 as it is set up as Domain Master -Browser. -</para> - -<para> -On each of the three networks, machines that are configured to -offer sharing services will broadcast that they are offering -these services. The local master browser on each subnet will -receive these broadcasts and keep a record of the fact that -the machine is offering a service. This list of records is -the basis of the browse list. For this case, assume that -all the machines are configured to offer services so all machines -will be on the browse list. -</para> - -<para> -For each network, the local master browser on that network is -considered 'authoritative' for all the names it receives via -local broadcast. This is because a machine seen by the local -master browser via a local broadcast must be on the same -network as the local master browser and thus is a 'trusted' -and 'verifiable' resource. Machines on other networks that -the local master browsers learn about when collating their -browse lists have not been directly seen - these records are -called 'non-authoritative'. -</para> - -<para> -At this point the browse lists look as follows (these are -the machines you would see in your network neighborhood if -you looked in it on a particular network right now). -</para> - -<para> -<programlisting> -Subnet Browse Master List ------- ------------- ---- -Subnet1 N1_C N1_A, N1_B, N1_C, N1_D, N1_E - -Subnet2 N2_B N2_A, N2_B, N2_C, N2_D - -Subnet3 N3_D N3_A, N3_B, N3_C, N3_D -</programlisting> -</para> - -<para> -Note that at this point all the subnets are separate, no -machine is seen across any of the subnets. -</para> - -<para> -Now examine subnet 2. As soon as N2_B has become the local -master browser it looks for a Domain master browser to synchronize -its browse list with. It does this by querying the WINS server -(N2_D) for the IP address associated with the NetBIOS name -WORKGROUP>1B<. This name was registerd by the Domain master -browser (N1_C) with the WINS server as soon as it was booted. -</para> - -<para> -Once N2_B knows the address of the Domain master browser it -tells it that is the local master browser for subnet 2 by -sending a MasterAnnouncement packet as a UDP port 138 packet. -It then synchronizes with it by doing a NetServerEnum2 call. This -tells the Domain Master Browser to send it all the server -names it knows about. Once the domain master browser receives -the MasterAnnouncement packet it schedules a synchronization -request to the sender of that packet. After both synchronizations -are done the browse lists look like : -</para> - -<para> -<programlisting> -Subnet Browse Master List ------- ------------- ---- -Subnet1 N1_C N1_A, N1_B, N1_C, N1_D, N1_E, - N2_A(*), N2_B(*), N2_C(*), N2_D(*) - -Subnet2 N2_B N2_A, N2_B, N2_C, N2_D - N1_A(*), N1_B(*), N1_C(*), N1_D(*), N1_E(*) - -Subnet3 N3_D N3_A, N3_B, N3_C, N3_D - -Servers with a (*) after them are non-authoritative names. -</programlisting> -</para> - -<para> -At this point users looking in their network neighborhood on -subnets 1 or 2 will see all the servers on both, users on -subnet 3 will still only see the servers on their own subnet. -</para> - -<para> -The same sequence of events that occured for N2_B now occurs -for the local master browser on subnet 3 (N3_D). When it -synchronizes browse lists with the domain master browser (N1_A) -it gets both the server entries on subnet 1, and those on -subnet 2. After N3_D has synchronized with N1_C and vica-versa -the browse lists look like. -</para> - -<para> -<programlisting> -Subnet Browse Master List ------- ------------- ---- -Subnet1 N1_C N1_A, N1_B, N1_C, N1_D, N1_E, - N2_A(*), N2_B(*), N2_C(*), N2_D(*), - N3_A(*), N3_B(*), N3_C(*), N3_D(*) - -Subnet2 N2_B N2_A, N2_B, N2_C, N2_D - N1_A(*), N1_B(*), N1_C(*), N1_D(*), N1_E(*) - -Subnet3 N3_D N3_A, N3_B, N3_C, N3_D - N1_A(*), N1_B(*), N1_C(*), N1_D(*), N1_E(*), - N2_A(*), N2_B(*), N2_C(*), N2_D(*) - -Servers with a (*) after them are non-authoritative names. -</programlisting> -</para> - -<para> -At this point users looking in their network neighborhood on -subnets 1 or 3 will see all the servers on all sunbets, users on -subnet 2 will still only see the servers on subnets 1 and 2, but not 3. -</para> - -<para> -Finally, the local master browser for subnet 2 (N2_B) will sync again -with the domain master browser (N1_C) and will recieve the missing -server entries. Finally - and as a steady state (if no machines -are removed or shut off) the browse lists will look like : -</para> - -<para> -<programlisting> -Subnet Browse Master List ------- ------------- ---- -Subnet1 N1_C N1_A, N1_B, N1_C, N1_D, N1_E, - N2_A(*), N2_B(*), N2_C(*), N2_D(*), - N3_A(*), N3_B(*), N3_C(*), N3_D(*) - -Subnet2 N2_B N2_A, N2_B, N2_C, N2_D - N1_A(*), N1_B(*), N1_C(*), N1_D(*), N1_E(*) - N3_A(*), N3_B(*), N3_C(*), N3_D(*) - -Subnet3 N3_D N3_A, N3_B, N3_C, N3_D - N1_A(*), N1_B(*), N1_C(*), N1_D(*), N1_E(*), - N2_A(*), N2_B(*), N2_C(*), N2_D(*) - -Servers with a (*) after them are non-authoritative names. -</programlisting> -</para> - -<para> -Synchronizations between the domain master browser and local -master browsers will continue to occur, but this should be a -steady state situation. -</para> - -<para> -If either router R1 or R2 fails the following will occur: -</para> - -<orderedlist> -<listitem> - <para> - Names of computers on each side of the inaccessible network fragments - will be maintained for as long as 36 minutes, in the network neighbourhood - lists. - </para> -</listitem> - -<listitem> - <para> - Attempts to connect to these inaccessible computers will fail, but the - names will not be removed from the network neighbourhood lists. - </para> -</listitem> - -<listitem> - <para> - If one of the fragments is cut off from the WINS server, it will only - be able to access servers on its local subnet, by using subnet-isolated - broadcast NetBIOS name resolution. The effects are similar to that of - losing access to a DNS server. - </para> -</listitem> -</orderedlist> -</sect2> -</sect1> - -<sect1> -<title>Setting up a WINS server</title> - -<para> -Either a Samba machine or a Windows NT Server machine may be set up -as a WINS server. To set a Samba machine to be a WINS server you must -add the following option to the &smb.conf; file on the selected machine : -in the [globals] section add the line -</para> - -<para> -<command> wins support = yes</command> -</para> - -<para> -Versions of Samba prior to 1.9.17 had this parameter default to -yes. If you have any older versions of Samba on your network it is -strongly suggested you upgrade to a recent version, or at the very -least set the parameter to 'no' on all these machines. -</para> - -<para> -Machines with <command>wins support = yes</command> will keep a list of -all NetBIOS names registered with them, acting as a DNS for NetBIOS names. -</para> - -<para> -You should set up only ONE wins server. Do NOT set the -<command>wins support = yes</command> option on more than one Samba -server. -</para> - -<para> -To set up a Windows NT Server as a WINS server you need to set up -the WINS service - see your NT documentation for details. Note that -Windows NT WINS Servers can replicate to each other, allowing more -than one to be set up in a complex subnet environment. As Microsoft -refuse to document these replication protocols Samba cannot currently -participate in these replications. It is possible in the future that -a Samba->Samba WINS replication protocol may be defined, in which -case more than one Samba machine could be set up as a WINS server -but currently only one Samba server should have the -<command>wins support = yes</command> parameter set. -</para> - -<para> -After the WINS server has been configured you must ensure that all -machines participating on the network are configured with the address -of this WINS server. If your WINS server is a Samba machine, fill in -the Samba machine IP address in the "Primary WINS Server" field of -the "Control Panel->Network->Protocols->TCP->WINS Server" dialogs -in Windows 95 or Windows NT. To tell a Samba server the IP address -of the WINS server add the following line to the [global] section of -all &smb.conf; files : -</para> - -<para> -<command>wins server = >name or IP address<</command> -</para> - -<para> -where >name or IP address< is either the DNS name of the WINS server -machine or its IP address. -</para> - -<para> -Note that this line MUST NOT BE SET in the &smb.conf; file of the Samba -server acting as the WINS server itself. If you set both the -<command>wins support = yes</command> option and the -<command>wins server = <name></command> option then -nmbd will fail to start. -</para> - -<para> -There are two possible scenarios for setting up cross subnet browsing. -The first details setting up cross subnet browsing on a network containing -Windows 95, Samba and Windows NT machines that are not configured as -part of a Windows NT Domain. The second details setting up cross subnet -browsing on networks that contain NT Domains. -</para> - -</sect1> - -<sect1> -<title>Setting up Browsing in a WORKGROUP</title> - -<para> -To set up cross subnet browsing on a network containing machines -in up to be in a WORKGROUP, not an NT Domain you need to set up one -Samba server to be the Domain Master Browser (note that this is *NOT* -the same as a Primary Domain Controller, although in an NT Domain the -same machine plays both roles). The role of a Domain master browser is -to collate the browse lists from local master browsers on all the -subnets that have a machine participating in the workgroup. Without -one machine configured as a domain master browser each subnet would -be an isolated workgroup, unable to see any machines on any other -subnet. It is the presense of a domain master browser that makes -cross subnet browsing possible for a workgroup. -</para> - -<para> -In an WORKGROUP environment the domain master browser must be a -Samba server, and there must only be one domain master browser per -workgroup name. To set up a Samba server as a domain master browser, -set the following option in the [global] section of the &smb.conf; file : -</para> - -<para> -<command>domain master = yes</command> -</para> - -<para> -The domain master browser should also preferrably be the local master -browser for its own subnet. In order to achieve this set the following -options in the [global] section of the &smb.conf; file : -</para> - -<para> -<programlisting> -domain master = yes -local master = yes -preferred master = yes -os level = 65 -</programlisting> -</para> - -<para> -The domain master browser may be the same machine as the WINS -server, if you require. -</para> - -<para> -Next, you should ensure that each of the subnets contains a -machine that can act as a local master browser for the -workgroup. Any MS Windows NT/2K/XP/2003 machine should be -able to do this, as will Windows 9x machines (although these -tend to get rebooted more often, so it's not such a good idea -to use these). To make a Samba server a local master browser -set the following options in the [global] section of the -&smb.conf; file : -</para> - -<para> -<programlisting> -domain master = no -local master = yes -preferred master = yes -os level = 65 -</programlisting> -</para> - -<para> -Do not do this for more than one Samba server on each subnet, -or they will war with each other over which is to be the local -master browser. -</para> - -<para> -The <command>local master</command> parameter allows Samba to act as a -local master browser. The <command>preferred master</command> causes nmbd -to force a browser election on startup and the <command>os level</command> -parameter sets Samba high enough so that it should win any browser elections. -</para> - -<para> -If you have an NT machine on the subnet that you wish to -be the local master browser then you can disable Samba from -becoming a local master browser by setting the following -options in the <command>[global]</command> section of the -&smb.conf; file : -</para> - -<para> -<programlisting> -domain master = no -local master = no -preferred master = no -os level = 0 -</programlisting> -</para> - -</sect1> - -<sect1> -<title>Setting up Browsing in a DOMAIN</title> - -<para> -If you are adding Samba servers to a Windows NT Domain then -you must not set up a Samba server as a domain master browser. -By default, a Windows NT Primary Domain Controller for a Domain -name is also the Domain master browser for that name, and many -things will break if a Samba server registers the Domain master -browser NetBIOS name (<replaceable>DOMAIN</replaceable><1B>) -with WINS instead of the PDC. -</para> - -<para> -For subnets other than the one containing the Windows NT PDC -you may set up Samba servers as local master browsers as -described. To make a Samba server a local master browser set -the following options in the <command>[global]</command> section -of the &smb.conf; file : -</para> - -<para> -<programlisting> -domain master = no -local master = yes -preferred master = yes -os level = 65 -</programlisting> -</para> - -<para> -If you wish to have a Samba server fight the election with machines -on the same subnet you may set the <command>os level</command> parameter -to lower levels. By doing this you can tune the order of machines that -will become local master browsers if they are running. For -more details on this see the section <link linkend="browse-force-master"> -Forcing samba to be the master browser</link> -below. -</para> - -<para> -If you have Windows NT machines that are members of the domain -on all subnets, and you are sure they will always be running then -you can disable Samba from taking part in browser elections and -ever becoming a local master browser by setting following options -in the <command>[global]</command> section of the &smb.conf; -file : -</para> - -<para> -<command> - domain master = no - local master = no - preferred master = no - os level = 0 -</command> -</para> - -</sect1> - -<sect1 id="browse-force-master"> -<title>Forcing samba to be the master</title> - -<para> -Who becomes the <command>master browser</command> is determined by an election -process using broadcasts. Each election packet contains a number of parameters -which determine what precedence (bias) a host should have in the -election. By default Samba uses a very low precedence and thus loses -elections to just about anyone else. -</para> - -<para> -If you want Samba to win elections then just set the <command>os level</command> global -option in &smb.conf; to a higher number. It defaults to 0. Using 34 -would make it win all elections over every other system (except other -samba systems!) -</para> - -<para> -A <command>os level</command> of 2 would make it beat WfWg and Win95, but not MS Windows -NT/2K Server. A MS Windows NT/2K Server domain controller uses level 32. -</para> - -<para>The maximum os level is 255</para> - -<para> -If you want samba to force an election on startup, then set the -<command>preferred master</command> global option in &smb.conf; to "yes". Samba will -then have a slight advantage over other potential master browsers -that are not preferred master browsers. Use this parameter with -care, as if you have two hosts (whether they are windows 95 or NT or -samba) on the same local subnet both set with <command>preferred master</command> to -"yes", then periodically and continually they will force an election -in order to become the local master browser. -</para> - -<para> -If you want samba to be a <command>domain master browser</command>, then it is -recommended that you also set <command>preferred master</command> to "yes", because -samba will not become a domain master browser for the whole of your -LAN or WAN if it is not also a local master browser on its own -broadcast isolated subnet. -</para> - -<para> -It is possible to configure two samba servers to attempt to become -the domain master browser for a domain. The first server that comes -up will be the domain master browser. All other samba servers will -attempt to become the domain master browser every 5 minutes. They -will find that another samba server is already the domain master -browser and will fail. This provides automatic redundancy, should -the current domain master browser fail. -</para> - -</sect1> - -<sect1> -<title>Making samba the domain master</title> - -<para> -The domain master is responsible for collating the browse lists of -multiple subnets so that browsing can occur between subnets. You can -make samba act as the domain master by setting <command>domain master = yes</command> -in &smb.conf;. By default it will not be a domain master. -</para> - -<para> -Note that you should NOT set Samba to be the domain master for a -workgroup that has the same name as an NT Domain. -</para> - -<para> -When samba is the domain master and the master browser it will listen -for master announcements (made roughly every twelve minutes) from local -master browsers on other subnets and then contact them to synchronise -browse lists. -</para> - -<para> -If you want samba to be the domain master then I suggest you also set -the <command>os level</command> high enough to make sure it wins elections, and set -<command>preferred master</command> to "yes", to get samba to force an election on -startup. -</para> - -<para> -Note that all your servers (including samba) and clients should be -using a WINS server to resolve NetBIOS names. If your clients are only -using broadcasting to resolve NetBIOS names, then two things will occur: -</para> - -<orderedlist> -<listitem> - <para> - your local master browsers will be unable to find a domain master - browser, as it will only be looking on the local subnet. - </para> -</listitem> - -<listitem> - <para> - if a client happens to get hold of a domain-wide browse list, and - a user attempts to access a host in that list, it will be unable to - resolve the NetBIOS name of that host. - </para> -</listitem> -</orderedlist> - -<para> -If, however, both samba and your clients are using a WINS server, then: -</para> - -<orderedlist> -<listitem> - <para> - your local master browsers will contact the WINS server and, as long as - samba has registered that it is a domain master browser with the WINS - server, your local master browser will receive samba's ip address - as its domain master browser. - </para> -</listitem> - -<listitem> - <para> - when a client receives a domain-wide browse list, and a user attempts - to access a host in that list, it will contact the WINS server to - resolve the NetBIOS name of that host. as long as that host has - registered its NetBIOS name with the same WINS server, the user will - be able to see that host. - </para> -</listitem> -</orderedlist> - -</sect1> - -<sect1> -<title>Note about broadcast addresses</title> - -<para> -If your network uses a "0" based broadcast address (for example if it -ends in a 0) then you will strike problems. Windows for Workgroups -does not seem to support a 0's broadcast and you will probably find -that browsing and name lookups won't work. -</para> -</sect1> - -<sect1> -<title>Multiple interfaces</title> - -<para> -Samba now supports machines with multiple network interfaces. If you -have multiple interfaces then you will need to use the <command>interfaces</command> -option in &smb.conf; to configure them. -</para> -</sect1> -</chapter> |