nmbd - NetBIOS name server to provide NetBIOS over IP naming services
nmbd [-D] [-F] [-S] [-a] [-i] [-o] [-h] [-V] [-d <debug level>]
[-H <lmhosts file>] [-l <log directory>] [-p <port number>]
[-s <configuration file>]
This program is part of the samba(7) suite.
nmbd is a server that understands and can reply to NetBIOS over IP name
service requests, like those produced by SMB/CIFS clients such as Win-
dows 95/98/ME, Windows NT, Windows 2000, Windows XP and LanManager
clients. It also participates in the browsing protocols which make up
the Windows "Network Neighborhood" view.
SMB/CIFS clients, when they start up, may wish to locate an SMB/CIFS
server. That is, they wish to know what IP number a specified host is
Amongst other services, nmbd will listen for such requests, and if its
own NetBIOS name is specified it will respond with the IP number of the
host it is running on. Its "own NetBIOS name" is by default the primary
DNS name of the host it is running on, but this can be overridden by
the netbios name in smb.conf. Thus nmbd will reply to broadcast queries
for its own name(s). Additional names for nmbd to respond on can be set
via parameters in the smb.conf(5) configuration file.
nmbd can also be used as a WINS (Windows Internet Name Server) server.
What this basically means is that it will act as a WINS database serv-
er, creating a database from name registration requests that it re-
ceives and replying to queries from clients for these names.
In addition, nmbd can act as a WINS proxy, relaying broadcast queries
from clients that do not understand how to talk the WINS protocol to a
-D If specified, this parameter causesnmbd to operate as a daemon.
That is, it detaches itself and runs in the background, fielding
requests on the appropriate port. By default, nmbd will operate
as a daemon if launched from a command shell. nmbd can also be
operated from the inetd meta-daemon, although this is not recom-
-F If specified, this parameter causes the main nmbd process to not
daemonize, i.e. double-fork and disassociate with the terminal.
Child processes are still created as normal to service each con-
nection request, but the main process does not exit. This opera-
tion mode is suitable for runningnmbd under process supervisors
such as supervise and svscan from Daniel J. Bernstein’s daemon-
tools package, or the AIX process monitor.
-S If specified, this parameter causesnmbd to log to standard out-
put rather than a file.
-i If this parameter is specified it causes the server to run "in-
teractively", not as a daemon, even if the server is executed on
the command line of a shell. Setting this parameter negates the
implicit daemon mode when run from the command line. nmbd also
logs to standard output, as if the -S parameter had been given.
Print a summary of command line options.
NetBIOS lmhosts file. The lmhosts file is a list of NetBIOS
names to IP addresses that is loaded by the nmbd server and used
via the name resolution mechanism name resolve order described
in smb.conf(5) to resolve any NetBIOS name queries needed by the
server. Note that the contents of this file are NOT used by nmbd
to answer any name queries. Adding a line to this file affects
name NetBIOS resolution from this host ONLY.
The default path to this file is compiled into Samba as part of
the build process. Common defaults are /usr/local/sam-
ba/lib/lmhosts,/usr/samba/lib/lmhosts or/etc/samba/lmhosts. See
the lmhosts(5) man page for details on the contents of this
-V Prints the program version number.
-s <configuration file>
The file specified contains the configuration details required
by the server. The information in this file includes server-spe-
cific information such as what printcap file to use, as well as
descriptions of all the services that the server is to provide.
See smb.conf for more information. The default configuration
file name is determined at compile time.
debuglevel is an integer from 0 to 10. The default value if this
parameter is not specified is zero.
The higher this value, the more detail will be logged to the log
files about the activities of the server. At level 0, only crit-
ical errors and serious warnings will be logged. Level 1 is a
reasonable level for day-to-day running - it generates a small
amount of information about operations carried out.
Levels above 1 will generate considerable amounts of log data,
and should only be used when investigating a problem. Levels
above 3 are designed for use only by developers and generate
HUGE amounts of log data, most of which is extremely cryptic.
Note that specifying this parameter here will override the pa-
rameter in the smb.conf file.
Base directory name for log/debug files. The extension ".prog-
name" will be appended (e.g. log.smbclient, log.smbd, etc...).
The log file is never removed by the client.
-p <UDP port number>
UDP port number is a positive integer value. This option changes
the default UDP port number (normally 137) that nmbd responds to
name queries on. Don’t use this option unless you are an expert,
in which case you won’t need help!
If the server is to be run by theinetd meta-daemon, this file
must contain suitable startup information for the meta-daemon.
or whatever initialization script your system uses).
If running the server as a daemon at startup, this file will
need to contain an appropriate startup sequence for the server.
If running the server via the meta-daemon inetd, this file must
contain a mapping of service name (e.g., netbios-ssn) to service
port (e.g., 139) and protocol type (e.g., tcp).
This is the default location of the smb.conf(5) server configu-
ration file. Other common places that systems install this file
are /usr/samba/lib/smb.conf and /etc/samba/smb.conf.
When run as a WINS server (see thewins support parameter in the
smb.conf(5) man page),nmbd will store the WINS database in the
file wins.dat in the var/locks directory configured under wher-
ever Samba was configured to install itself.
If nmbd is acting as a browse master (see the local master pa-
rameter in the smb.conf(5) man page, nmbd will store the brows-
ing database in the file browse.dat in the var/locks directory
configured under wherever Samba was configured to install it-
To shut down an nmbd process it is recommended that SIGKILL (-9) NOT be
used, except as a last resort, as this may leave the name database in
an inconsistent state. The correct way to terminate nmbd is to send it
a SIGTERM (-15) signal and wait for it to die on its own.
nmbd will accept SIGHUP, which will cause it to dump out its namelists
into the file namelist.debug in the /usr/local/samba/var/locks direc-
tory (or the var/locks directory configured under wherever Samba was
configured to install itself). This will also cause nmbd to dump out
its server database in the log.nmb file.
The debug log level of nmbd may be raised or lowered using smbcon-
trol(1) (SIGUSR[1|2] signals are no longer used since Samba 2.2). This
is to allow transient problems to be diagnosed, whilst still running at
a normally low log level.
This man page is correct for version 3.0 of the Samba suite.
inetd(8), smbd(8), smb.conf(5), smbclient(1), testparm(1), testprns(1),
and the Internet RFC’s rfc1001.txt, rfc1002.txt. In addition the CIFS
(formerly SMB) specification is available as a link from the Web page
The original Samba software and related utilities were created by An-
drew Tridgell. Samba is now developed by the Samba Team as an Open
Source project similar to the way the Linux kernel is developed.
The original Samba man pages were written by Karl Auer. The man page
sources were converted to YODL format (another excellent piece of Open
Source software, available at ftp://ftp.icce.rug.nl/pub/unix/) and up-
dated for the Samba 2.0 release by Jeremy Allison. The conversion to
DocBook for Samba 2.2 was done by Gerald Carter. The conversion to Doc-
Book XML 4.2 for Samba 3.0 was done by Alexander Bokovoy.
Man(1) output converted with