Network browsing is a concept that
enables Windows and Samba servers to appear in the Windows
Network Neighborhood. Inside the Network Neighborhood, icons are represented as
servers and if opened, the server's shares and printers that are
available are displayed.
Network browsing capabilities require NetBIOS over TCP/IP.
NetBIOS-based networking uses broadcast (UDP) messaging to
accomplish browse list management. Without NetBIOS and WINS as the
primary method for TCP/IP hostname resolution, other methods such
as static files (/etc/hosts) or DNS, must
be used.
A domain master browser collates the browse lists from local
master browsers on all subnets so that browsing can occur between
workgroups and subnets. Also, the domain master browser should
preferably be the local master browser for its own subnet.
For each workgroup, there must be one and only one domain master
browser. You can have one local master browser per subnet without a
domain master browser, but this results in isolated workgroups
unable to see each other. To resolve NetBIOS names in cross-subnet
workgroups, WINS is required.
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Note |
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The Domain Master Browser can be the same machine as the WINS
server.
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There can only be one domain master browser per workgroup name.
Here is an example of the smb.conf file
in which the Samba server is a domain master browser:
[global]
domain master = Yes
local master = Yes
preferred master = Yes
os level = 35
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Next is an example of the smb.conf
file in which the Samba server is a local master browser:
[global]
domain master = no
local master = Yes
preferred master = Yes
os level = 35
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The os level directive operates as a
priority system for master browsers in a subnet. Setting different
values ensures master browsers do not conflict with each other for
authority.
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Tip |
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Lowering the os level directive results
in Samba conflicting with other master browsers on the same subnet.
The higher the value, the higher the priority. The highest a
Windows server can operate at is 32. This is a good way of tuning
multiple local master browsers.
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There are instances when a Windows NT machine on the subnet
could be the local master browser. The following is an example
smb.conf configuration in which the Samba
server is not serving in any browsing capacity:
[global]
domain master = no
local master = no
preferred master = no
os level = 0
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Warning |
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Having multiple local master browsers result in each server
competing for browsing election requests. Make sure there is only
one local master browser per subnet.
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By default, a Windows NT PDC for a domain is also the domain
master browser for that domain. A Samba server must be set up as a
domain master server in this type of situation. Network browsing
may fail if the Samba server is running WINS along with other
domain controllers in operation.
For subnets that do not include the Windows NT PDC, a Samba
server can be implemented as a local master browser. Configuring
the smb.conf for a local master browser
(or no browsing at all) in a domain controller environment is the
same as workgroup configuration.
Either a Samba server or a Windows NT server can function as a
WINS server. When a WINS server is used with NetBIOS enabled, UDP
unicasts can be routed which allows name resolution across
networks. Without a WINS server, the UDP broadcast is limited to
the local subnet and therefore cannot be routed to other subnets,
workgroups, or domains. If WINS replication is necessary, do not
use Samba as your primary WINS server, as Samba does not currently
support WINS replication.
In a mixed NT/2000/2003 server and Samba environment, it is
recommended that you use the Microsoft WINS capabilities. In a
Samba-only environment, it is recommended that you use only one Samba server for WINS.
The following is an example of the smb.conf file in which the Samba server is serving
as a WINS server:
[global]
wins support = Yes
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Tip |
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All servers (including Samba) should connect to a WINS server to
resolve NetBIOS names. Without WINS, browsing only occurs on the
local subnet. Furthermore, even if a domain-wide list is somehow
obtained, hosts are not resolvable for the client without WINS.
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