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SMBD(8)			  System Administration tools		       SMBD(8)



NAME
       smbd - server to provide SMB/CIFS services to clients

SYNOPSIS
       smbd [-D|--daemon] [-F|--foreground] [-S|--log-stdout]
	[-i|--interactive] [-V] [-b|--build-options] [-d <debug level>]
	[-l|--log-basename <log directory>] [-p <port number(s)>]
	[-P <profiling level>] [-s <configuration file>] [--no-process-group]

DESCRIPTION
       This program is part of the samba(7) suite.

       smbd is the server daemon that provides filesharing and printing
       services to Windows clients. The server provides filespace and printer
       services to clients using the SMB (or CIFS) protocol. This is
       compatible with the LanManager protocol, and can service LanManager
       clients. These include MSCLIENT 3.0 for DOS, Windows for Workgroups,
       Windows 95/98/ME, Windows NT, Windows 2000, OS/2, DAVE for Macintosh,
       and smbfs for Linux.

       An extensive description of the services that the server can provide is
       given in the man page for the configuration file controlling the
       attributes of those services (see smb.conf(5). This man page will not
       describe the services, but will concentrate on the administrative
       aspects of running the server.

       Please note that there are significant security implications to running
       this server, and the smb.conf(5) manual page should be regarded as
       mandatory reading before proceeding with installation.

       A session is created whenever a client requests one. Each client gets a
       copy of the server for each session. This copy then services all
       connections made by the client during that session. When all
       connections from its client are closed, the copy of the server for that
       client terminates.

       The configuration file, and any files that it includes, are
       automatically reloaded every minute, if they change. You can force a
       reload by sending a SIGHUP to the server. Reloading the configuration
       file will not affect connections to any service that is already
       established. Either the user will have to disconnect from the service,
       or smbd killed and restarted.

OPTIONS
       -D|--daemon
	   If specified, this parameter causes the server to operate as a
	   daemon. That is, it detaches itself and runs in the background,
	   fielding requests on the appropriate port. Operating the server as
	   a daemon is the recommended way of running smbd for servers that
	   provide more than casual use file and print services. This switch
	   is assumed if smbd is executed on the command line of a shell.

       -F|--foreground
	   If specified, this parameter causes the main smbd process to not
	   daemonize, i.e. double-fork and disassociate with the terminal.
	   Child processes are still created as normal to service each
	   connection request, but the main process does not exit. This
	   operation mode is suitable for running smbd under process
	   supervisors such as supervise and svscan from Daniel J. Bernstein's
	   daemontools package, or the AIX process monitor.

       -S|--log-stdout
	   If specified, this parameter causes smbd to log to standard output
	   rather than a file.

       -i|--interactive
	   If this parameter is specified it causes the server to run
	   "interactively", 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.	 smbd will
	   only accept one connection and terminate. It will also log to
	   standard output, as if the -S parameter had been given.

       -d|--debuglevel=level
	   level is an integer from 0 to 10. The default value if this
	   parameter is not specified is 0.

	   The higher this value, the more detail will be logged to the log
	   files about the activities of the server. At level 0, only critical
	   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 log
	   level parameter in the smb.conf file.

       -V|--version
	   Prints the program version number.

       -s|--configfile=<configuration file>
	   The file specified contains the configuration details required by
	   the server. The information in this file includes server-specific
	   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.

       -l|--log-basename=logdirectory
	   Base directory name for log/debug files. The extension ".progname"
	   will be appended (e.g. log.smbclient, log.smbd, etc...). The log
	   file is never removed by the client.

       --option=<name>=<value>
	   Set the smb.conf(5) option "<name>" to value "<value>" from the
	   command line. This overrides compiled-in defaults and options read
	   from the configuration file.

       -?|--help
	   Print a summary of command line options.

       --usage
	   Display brief usage message.

       --no-process-group
	   Do not create a new process group for smbd.

       -b|--build-options
	   Prints information about how Samba was built.

       -p|--port<port number(s)>
	   port number(s) is a space or comma-separated list of TCP ports smbd
	   should listen on. The default value is taken from the ports
	   parameter in smb.conf

	   The default ports are 139 (used for SMB over NetBIOS over TCP) and
	   port 445 (used for plain SMB over TCP).

       -P|--profiling-level<profiling level>
	   profiling level is a number specifying the level of profiling data
	   to be collected. 0 turns off profiling, 1 turns on counter
	   profiling only, 2 turns on complete profiling, and 3 resets all
	   profiling data.

FILES
       /etc/inetd.conf
	   If the server is to be run by the inetd meta-daemon, this file must
	   contain suitable startup information for the meta-daemon.

       /etc/rc
	   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.

       /etc/services
	   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).

       /usr/local/samba/lib/smb.conf
	   This is the default location of the smb.conf(5) server
	   configuration file. Other common places that systems install this
	   file are /usr/samba/lib/smb.conf and /etc/samba/smb.conf.

	   This file describes all the services the server is to make
	   available to clients. See smb.conf(5) for more information.

LIMITATIONS
       On some systems smbd cannot change uid back to root after a setuid()
       call. Such systems are called trapdoor uid systems. If you have such a
       system, you will be unable to connect from a client (such as a PC) as
       two different users at once. Attempts to connect the second user will
       result in access denied or similar.

ENVIRONMENT VARIABLES
       PRINTER
	   If no printer name is specified to printable services, most systems
	   will use the value of this variable (or lp if this variable is not
	   defined) as the name of the printer to use. This is not specific to
	   the server, however.

PAM INTERACTION
       Samba uses PAM for authentication (when presented with a plaintext
       password), for account checking (is this account disabled?) and for
       session management. The degree too which samba supports PAM is
       restricted by the limitations of the SMB protocol and the obey pam
       restrictionssmb.conf(5) parameter. When this is set, the following
       restrictions apply:

	      o	  Account Validation: All accesses to a samba server are
		  checked against PAM to see if the account is valid, not
		  disabled and is permitted to login at this time. This also
		  applies to encrypted logins.

	      o	  Session Management: When not using share level security,
		  users must pass PAM's session checks before access is
		  granted. Note however, that this is bypassed in share level
		  security. Note also that some older pam configuration files
		  may need a line added for session support.

VERSION
       This man page is part of version 4.8.3 of the Samba suite.

DIAGNOSTICS
       Most diagnostics issued by the server are logged in a specified log
       file. The log file name is specified at compile time, but may be
       overridden on the command line.

       The number and nature of diagnostics available depends on the debug
       level used by the server. If you have problems, set the debug level to
       3 and peruse the log files.

       Most messages are reasonably self-explanatory. Unfortunately, at the
       time this man page was created, there are too many diagnostics
       available in the source code to warrant describing each and every
       diagnostic. At this stage your best bet is still to grep the source
       code and inspect the conditions that gave rise to the diagnostics you
       are seeing.

TDB FILES
       Samba stores it's data in several TDB (Trivial Database) files, usually
       located in /var/lib/samba.

       (*) information persistent across restarts (but not necessarily
       important to backup).

       account_policy.tdb*
	   NT account policy settings such as pw expiration, etc...

       brlock.tdb
	   byte range locks

       browse.dat
	   browse lists

       gencache.tdb
	   generic caching db

       group_mapping.tdb*
	   group mapping information

       locking.tdb
	   share modes & oplocks

       login_cache.tdb*
	   bad pw attempts

       messages.tdb
	   Samba messaging system

       netsamlogon_cache.tdb*
	   cache of user net_info_3 struct from net_samlogon() request (as a
	   domain member)

       ntdrivers.tdb*
	   installed printer drivers

       ntforms.tdb*
	   installed printer forms

       ntprinters.tdb*
	   installed printer information

       printing/
	   directory containing tdb per print queue of cached lpq output

       registry.tdb
	   Windows registry skeleton (connect via regedit.exe)

       smbXsrv_session_global.tdb
	   session information (e.g. support for 'utmp = yes')

       smbXsrv_tcon_global.tdb
	   share connections (used to enforce max connections, etc...)

       smbXsrv_open_global.tdb
	   open file handles (used durable handles, etc...)

       share_info.tdb*
	   share acls

       winbindd_cache.tdb
	   winbindd's cache of user lists, etc...

       winbindd_idmap.tdb*
	   winbindd's local idmap db

       wins.dat*
	   wins database when 'wins support = yes'

SIGNALS
       Sending the smbd a SIGHUP will cause it to reload its smb.conf
       configuration file within a short period of time.

       To shut down a user's smbd process it is recommended that SIGKILL
       (-9)NOT be used, except as a last resort, as this may leave the shared
       memory area in an inconsistent state. The safe way to terminate an smbd
       is to send it a SIGTERM (-15) signal and wait for it to die on its own.

       The debug log level of smbd may be raised or lowered using
       smbcontrol(1) program (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.

       Note that as the signal handlers send a debug write, they are not
       re-entrant in smbd. This you should wait until smbd is in a state of
       waiting for an incoming SMB before issuing them. It is possible to make
       the signal handlers safe by un-blocking the signals before the select
       call and re-blocking them after, however this would affect performance.

SEE ALSO
       hosts_access(5), inetd(8), nmbd(8), smb.conf(5), smbclient(1),
       testparm(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 https://www.samba.org/cifs/.

AUTHOR
       The original Samba software and related utilities were created by
       Andrew Tridgell. Samba is now developed by the Samba Team as an Open
       Source project similar to the way the Linux kernel is developed.



Samba 4.8.3			  01/09/2019			       SMBD(8)