1SMBD(8) System Administration tools SMBD(8)
2
6 smbd - server to provide SMB/CIFS services to clients
7
9 smbd [-D|--daemon] [-F|--foreground] [-S|--log-stdout]
10 [-i|--interactive] [-V] [-b|--build-options] [-d <debug level>]
11 [-l|--log-basename <log directory>] [-p <port number(s)>]
12 [-P <profiling level>] [-s <configuration file>] [--no-process-group]
13
15 This program is part of the samba(7) suite.
16 smbd is the server daemon that provides filesharing and printing
18 services to Windows clients. The server provides filespace and printer
19 services to clients using the SMB (or CIFS) protocol. This is
20 compatible with the LanManager protocol, and can service LanManager
21 clients. These include MSCLIENT 3.0 for DOS, Windows for Workgroups,
22 Windows 95/98/ME, Windows NT, Windows 2000, OS/2, DAVE for Macintosh,
23 and smbfs for Linux.
24 An extensive description of the services that the server can provide is
26 given in the man page for the configuration file controlling the
27 attributes of those services (see smb.conf(5). This man page will not
28 describe the services, but will concentrate on the administrative
29 aspects of running the server.
30 Please note that there are significant security implications to running
32 this server, and the smb.conf(5) manual page should be regarded as
33 mandatory reading before proceeding with installation.
34 A session is created whenever a client requests one. Each client gets a
36 copy of the server for each session. This copy then services all
37 connections made by the client during that session. When all
38 connections from its client are closed, the copy of the server for that
39 client terminates.
40 The configuration file, and any files that it includes, are
42 automatically reloaded every three minutes, if they change. One can
43 force a reload by sending a SIGHUP to the server. Reloading the
44 configuration file will not affect connections to any service that is
45 already established. Either the user will have to disconnect from the
46 service, or smbd killed and restarted.
47 Instead of sending a SIGHUP signal, a request to reload configuration
49 file may be sent using smbcontrol(1) program.
50
52 -D|--daemon
53 If specified, this parameter causes the server to operate as a
54 daemon. That is, it detaches itself and runs in the background,
55 fielding requests on the appropriate port. Operating the server as
56 a daemon is the recommended way of running smbd for servers that
57 provide more than casual use file and print services. This switch
58 is assumed if smbd is executed on the command line of a shell.
59 -F|--foreground
61 If specified, this parameter causes the main smbd process to not
62 daemonize, i.e. double-fork and disassociate with the terminal.
63 Child processes are still created as normal to service each
64 connection request, but the main process does not exit. This
65 operation mode is suitable for running smbd under process
66 supervisors such as supervise and svscan from Daniel J. Bernstein's
67 daemontools package, or the AIX process monitor.
68 -S|--log-stdout
70 If specified, this parameter causes smbd to log to standard output
71 rather than a file.
72 -i|--interactive
74 If this parameter is specified it causes the server to run
75 "interactively", not as a daemon, even if the server is executed on
76 the command line of a shell. Setting this parameter negates the
77 implicit daemon mode when run from the command line. smbd will
78 only accept one connection and terminate. It will also log to
79 standard output, as if the -S parameter had been given.
80 -d|--debuglevel=level
82 level is an integer from 0 to 10. The default value if this
83 parameter is not specified is 0.
84 The higher this value, the more detail will be logged to the log
86 files about the activities of the server. At level 0, only critical
87 errors and serious warnings will be logged. Level 1 is a reasonable
88 level for day-to-day running - it generates a small amount of
89 information about operations carried out.
90 Levels above 1 will generate considerable amounts of log data, and
92 should only be used when investigating a problem. Levels above 3
93 are designed for use only by developers and generate HUGE amounts
94 of log data, most of which is extremely cryptic.
95 Note that specifying this parameter here will override the log
97 level parameter in the smb.conf file.
98 -V|--version
100 Prints the program version number.
101 -s|--configfile=<configuration file>
103 The file specified contains the configuration details required by
104 the server. The information in this file includes server-specific
105 information such as what printcap file to use, as well as
106 descriptions of all the services that the server is to provide. See
107 smb.conf for more information. The default configuration file name
108 is determined at compile time.
109 -l|--log-basename=logdirectory
111 Base directory name for log/debug files. The extension ".progname"
112 will be appended (e.g. log.smbclient, log.smbd, etc...). The log
113 file is never removed by the client.
114 --option=<name>=<value>
116 Set the smb.conf(5) option "<name>" to value "<value>" from the
117 command line. This overrides compiled-in defaults and options read
118 from the configuration file.
119 -?|--help
121 Print a summary of command line options.
122 --usage
124 Display brief usage message.
125 --no-process-group
127 Do not create a new process group for smbd.
128 -b|--build-options
130 Prints information about how Samba was built.
131 -p|--port<port number(s)>
133 port number(s) is a space or comma-separated list of TCP ports smbd
134 should listen on. The default value is taken from the ports
135 parameter in smb.conf
136 The default ports are 139 (used for SMB over NetBIOS over TCP) and
138 port 445 (used for plain SMB over TCP).
139 -P|--profiling-level<profiling level>
141 profiling level is a number specifying the level of profiling data
142 to be collected. 0 turns off profiling, 1 turns on counter
143 profiling only, 2 turns on complete profiling, and 3 resets all
144 profiling data.
145
147 /etc/inetd.conf
148 If the server is to be run by the inetd meta-daemon, this file must
149 contain suitable startup information for the meta-daemon.
150 /etc/rc
152 or whatever initialization script your system uses).
153 If running the server as a daemon at startup, this file will need
155 to contain an appropriate startup sequence for the server.
156 /etc/services
158 If running the server via the meta-daemon inetd, this file must
159 contain a mapping of service name (e.g., netbios-ssn) to service
160 port (e.g., 139) and protocol type (e.g., tcp).
161 /usr/local/samba/lib/smb.conf
163 This is the default location of the smb.conf(5) server
164 configuration file. Other common places that systems install this
165 file are /usr/samba/lib/smb.conf and /etc/samba/smb.conf.
166 This file describes all the services the server is to make
168 available to clients. See smb.conf(5) for more information.
169
171 On some systems smbd cannot change uid back to root after a setuid()
172 call. Such systems are called trapdoor uid systems. If you have such a
173 system, you will be unable to connect from a client (such as a PC) as
174 two different users at once. Attempts to connect the second user will
175 result in access denied or similar.
176
178 PRINTER
179 If no printer name is specified to printable services, most systems
180 will use the value of this variable (or lp if this variable is not
181 defined) as the name of the printer to use. This is not specific to
182 the server, however.
183
185 Samba uses PAM for authentication (when presented with a plaintext
186 password), for account checking (is this account disabled?) and for
187 session management. The degree too which samba supports PAM is
188 restricted by the limitations of the SMB protocol and the obey pam
189 restrictions smb.conf(5) parameter. When this is set, the following
190 restrictions apply:
191 • Account Validation: All accesses to a samba server are
193 checked against PAM to see if the account is valid, not
194 disabled and is permitted to login at this time. This also
195 applies to encrypted logins.
196 • Session Management: When not using share level security,
198 users must pass PAM's session checks before access is
199 granted. Note however, that this is bypassed in share level
200 security. Note also that some older pam configuration files
201 may need a line added for session support.
202
204 This man page is part of version 4.14.5 of the Samba suite.
205
207 Most diagnostics issued by the server are logged in a specified log
208 file. The log file name is specified at compile time, but may be
209 overridden on the command line.
210 The number and nature of diagnostics available depends on the debug
212 level used by the server. If you have problems, set the debug level to
213 3 and peruse the log files.
214 Most messages are reasonably self-explanatory. Unfortunately, at the
216 time this man page was created, there are too many diagnostics
217 available in the source code to warrant describing each and every
218 diagnostic. At this stage your best bet is still to grep the source
219 code and inspect the conditions that gave rise to the diagnostics you
220 are seeing.
221
223 Samba stores it's data in several TDB (Trivial Database) files, usually
224 located in /var/lib/samba.
225 (*) information persistent across restarts (but not necessarily
227 important to backup).
228 account_policy.tdb*
230 NT account policy settings such as pw expiration, etc...
231 brlock.tdb
233 byte range locks
234 browse.dat
236 browse lists
237 gencache.tdb
239 generic caching db
240 group_mapping.tdb*
242 group mapping information
243 locking.tdb
245 share modes & oplocks
246 login_cache.tdb*
248 bad pw attempts
249 messages.tdb
251 Samba messaging system
252 netsamlogon_cache.tdb*
254 cache of user net_info_3 struct from net_samlogon() request (as a
255 domain member)
256 ntdrivers.tdb*
258 installed printer drivers
259 ntforms.tdb*
261 installed printer forms
262 ntprinters.tdb*
264 installed printer information
265 printing/
267 directory containing tdb per print queue of cached lpq output
268 registry.tdb
270 Windows registry skeleton (connect via regedit.exe)
271 smbXsrv_session_global.tdb
273 session information (e.g. support for 'utmp = yes')
274 smbXsrv_tcon_global.tdb
276 share connections (used to enforce max connections, etc...)
277 smbXsrv_open_global.tdb
279 open file handles (used durable handles, etc...)
280 share_info.tdb*
282 share acls
283 winbindd_cache.tdb
285 winbindd's cache of user lists, etc...
286 winbindd_idmap.tdb*
288 winbindd's local idmap db
289 wins.dat*
291 wins database when 'wins support = yes'
292
294 Sending the smbd a SIGHUP will cause it to reload its smb.conf
295 configuration file within a short period of time.
296 To shut down a user's smbd process it is recommended that SIGKILL (-9)
298 NOT be used, except as a last resort, as this may leave the shared
299 memory area in an inconsistent state. The safe way to terminate an smbd
300 is to send it a SIGTERM (-15) signal and wait for it to die on its own.
301 The debug log level of smbd may be raised or lowered using
303 smbcontrol(1) program (SIGUSR[1|2] signals are no longer used since
304 Samba 2.2). This is to allow transient problems to be diagnosed, whilst
305 still running at a normally low log level.
306 Note that as the signal handlers send a debug write, they are not
308 re-entrant in smbd. This you should wait until smbd is in a state of
309 waiting for an incoming SMB before issuing them. It is possible to make
310 the signal handlers safe by un-blocking the signals before the select
311 call and re-blocking them after, however this would affect performance.
312
314 hosts_access(5), inetd(8), nmbd(8), smb.conf(5), smbclient(1),
315 testparm(1), and the Internet RFC's rfc1001.txt, rfc1002.txt. In
316 addition the CIFS (formerly SMB) specification is available as a link
317 from the Web page https://www.samba.org/cifs/.
318
320 The original Samba software and related utilities were created by
321 Andrew Tridgell. Samba is now developed by the Samba Team as an Open
322 Source project similar to the way the Linux kernel is developed.
323Samba 4.14.5 06/01/2021 SMBD(8)