1 <?xml version="1.0" encoding="iso-8859-1"?>
2 <!DOCTYPE refentry PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">
6 <refentrytitle>smbd</refentrytitle>
7 <manvolnum>8</manvolnum>
8 <refmiscinfo class="source">Samba</refmiscinfo>
9 <refmiscinfo class="manual">System Administration tools</refmiscinfo>
10 <refmiscinfo class="version">3.6</refmiscinfo>
15 <refname>smbd</refname>
16 <refpurpose>server to provide SMB/CIFS services to clients</refpurpose>
21 <command>smbd</command>
22 <arg choice="opt">-D</arg>
23 <arg choice="opt">-F</arg>
24 <arg choice="opt">-S</arg>
25 <arg choice="opt">-i</arg>
26 <arg choice="opt">-h</arg>
27 <arg choice="opt">-V</arg>
28 <arg choice="opt">-b</arg>
29 <arg choice="opt">-d <debug level></arg>
30 <arg choice="opt">-l <log directory></arg>
31 <arg choice="opt">-p <port number(s)></arg>
32 <arg choice="opt">-P <profiling level></arg>
33 <arg choice="opt">-O <socket option></arg>
34 <arg choice="opt">-s <configuration file></arg>
39 <title>DESCRIPTION</title>
40 <para>This program is part of the <citerefentry><refentrytitle>samba</refentrytitle>
41 <manvolnum>7</manvolnum></citerefentry> suite.</para>
43 <para><command>smbd</command> is the server daemon that
44 provides filesharing and printing services to Windows clients.
45 The server provides filespace and printer services to
46 clients using the SMB (or CIFS) protocol. This is compatible
47 with the LanManager protocol, and can service LanManager
48 clients. These include MSCLIENT 3.0 for DOS, Windows for
49 Workgroups, Windows 95/98/ME, Windows NT, Windows 2000,
50 OS/2, DAVE for Macintosh, and smbfs for Linux.</para>
52 <para>An extensive description of the services that the
53 server can provide is given in the man page for the
54 configuration file controlling the attributes of those
55 services (see <citerefentry><refentrytitle>smb.conf</refentrytitle>
56 <manvolnum>5</manvolnum></citerefentry>. This man page will not describe the
57 services, but will concentrate on the administrative aspects
58 of running the server.</para>
60 <para>Please note that there are significant security
61 implications to running this server, and the <citerefentry><refentrytitle>smb.conf</refentrytitle>
62 <manvolnum>5</manvolnum></citerefentry> manual page should be regarded as mandatory reading before
63 proceeding with installation.</para>
65 <para>A session is created whenever a client requests one.
66 Each client gets a copy of the server for each session. This
67 copy then services all connections made by the client during
68 that session. When all connections from its client are closed,
69 the copy of the server for that client terminates.</para>
71 <para>The configuration file, and any files that it includes,
72 are automatically reloaded every minute, if they change. You
73 can force a reload by sending a SIGHUP to the server. Reloading
74 the configuration file will not affect connections to any service
75 that is already established. Either the user will have to
76 disconnect from the service, or <command>smbd</command> killed and restarted.</para>
80 <title>OPTIONS</title>
85 <listitem><para>If specified, this parameter causes
86 the server to operate as a daemon. That is, it detaches
87 itself and runs in the background, fielding requests
88 on the appropriate port. Operating the server as a
89 daemon is the recommended way of running <command>smbd</command> for
90 servers that provide more than casual use file and
91 print services. This switch is assumed if <command>smbd
92 </command> is executed on the command line of a shell.
98 <listitem><para>If specified, this parameter causes
99 the main <command>smbd</command> process to not daemonize,
100 i.e. double-fork and disassociate with the terminal.
101 Child processes are still created as normal to service
102 each connection request, but the main process does not
103 exit. This operation mode is suitable for running
104 <command>smbd</command> under process supervisors such
105 as <command>supervise</command> and <command>svscan</command>
106 from Daniel J. Bernstein's <command>daemontools</command>
107 package, or the AIX process monitor.
113 <listitem><para>If specified, this parameter causes
114 <command>smbd</command> to log to standard output rather
115 than a file.</para></listitem>
120 <listitem><para>If this parameter is specified it causes the
121 server to run "interactively", not as a daemon, even if the
122 server is executed on the command line of a shell. Setting this
123 parameter negates the implicit daemon mode when run from the
124 command line. <command>smbd</command> also logs to standard
125 output, as if the <command>-S</command> parameter had been
130 &stdarg.server.debug;
136 <listitem><para>Prints information about how
137 Samba was built.</para></listitem>
141 <term>-p|--port<port number(s)></term>
142 <listitem><para><replaceable>port number(s)</replaceable> is a
143 space or comma-separated list of TCP ports smbd should listen on.
144 The default value is taken from the <smbconfoption name="ports"/> parameter in &smb.conf;</para>
146 <para>The default ports are 139 (used for SMB over NetBIOS over TCP)
147 and port 445 (used for plain SMB over TCP).
152 <term>-P|--profiling-level<profiling level></term>
153 <listitem><para><replaceable>profiling level</replaceable> is a
154 number specifying the level of profiling data to be collected.
155 0 turns off profiling, 1 turns on counter profiling only,
156 2 turns on complete profiling, and 3 resets all profiling data.
167 <term><filename>/etc/inetd.conf</filename></term>
168 <listitem><para>If the server is to be run by the
169 <command>inetd</command> meta-daemon, this file
170 must contain suitable startup information for the
176 <term><filename>/etc/rc</filename></term>
177 <listitem><para>or whatever initialization script your
180 <para>If running the server as a daemon at startup,
181 this file will need to contain an appropriate startup
182 sequence for the server. </para></listitem>
186 <term><filename>/etc/services</filename></term>
187 <listitem><para>If running the server via the
188 meta-daemon <command>inetd</command>, this file
189 must contain a mapping of service name (e.g., netbios-ssn)
190 to service port (e.g., 139) and protocol type (e.g., tcp).
195 <term><filename>/usr/local/samba/lib/smb.conf</filename></term>
196 <listitem><para>This is the default location of the <citerefentry><refentrytitle>smb.conf</refentrytitle>
197 <manvolnum>5</manvolnum></citerefentry> server configuration file. Other common places that systems
198 install this file are <filename>/usr/samba/lib/smb.conf</filename>
199 and <filename>/etc/samba/smb.conf</filename>.</para>
201 <para>This file describes all the services the server
202 is to make available to clients. See <citerefentry><refentrytitle>smb.conf</refentrytitle>
203 <manvolnum>5</manvolnum></citerefentry> for more information.</para>
210 <title>LIMITATIONS</title>
211 <para>On some systems <command>smbd</command> cannot change uid back
212 to root after a setuid() call. Such systems are called
213 trapdoor uid systems. If you have such a system,
214 you will be unable to connect from a client (such as a PC) as
215 two different users at once. Attempts to connect the
216 second user will result in access denied or
221 <title>ENVIRONMENT VARIABLES</title>
225 <term><envar>PRINTER</envar></term>
226 <listitem><para>If no printer name is specified to
227 printable services, most systems will use the value of
228 this variable (or <constant>lp</constant> if this variable is
229 not defined) as the name of the printer to use. This
230 is not specific to the server, however.</para></listitem>
237 <title>PAM INTERACTION</title>
238 <para>Samba uses PAM for authentication (when presented with a plaintext
239 password), for account checking (is this account disabled?) and for
240 session management. The degree too which samba supports PAM is restricted
241 by the limitations of the SMB protocol and the <smbconfoption name="obey pam restrictions"/> <citerefentry><refentrytitle>smb.conf</refentrytitle>
242 <manvolnum>5</manvolnum></citerefentry> parameter. When this is set, the following restrictions apply:
246 <listitem><para><emphasis>Account Validation</emphasis>: All accesses to a
247 samba server are checked
248 against PAM to see if the account is valid, not disabled and is permitted to
249 login at this time. This also applies to encrypted logins.
252 <listitem><para><emphasis>Session Management</emphasis>: When not using share
253 level security, users must pass PAM's session checks before access
254 is granted. Note however, that this is bypassed in share level security.
255 Note also that some older pam configuration files may need a line
256 added for session support.
262 <title>VERSION</title>
264 <para>This man page is correct for version 3 of
265 the Samba suite.</para>
269 <title>DIAGNOSTICS</title>
271 <para>Most diagnostics issued by the server are logged
272 in a specified log file. The log file name is specified
273 at compile time, but may be overridden on the command line.</para>
275 <para>The number and nature of diagnostics available depends
276 on the debug level used by the server. If you have problems, set
277 the debug level to 3 and peruse the log files.</para>
279 <para>Most messages are reasonably self-explanatory. Unfortunately,
280 at the time this man page was created, there are too many diagnostics
281 available in the source code to warrant describing each and every
282 diagnostic. At this stage your best bet is still to grep the
283 source code and inspect the conditions that gave rise to the
284 diagnostics you are seeing.</para>
288 <title>TDB FILES</title>
290 <para>Samba stores it's data in several TDB (Trivial Database) files, usually located in <filename>/var/lib/samba</filename>.</para>
293 (*) information persistent across restarts (but not
294 necessarily important to backup).
298 <varlistentry><term>account_policy.tdb*</term>
300 <para>NT account policy settings such as pw expiration, etc...</para>
304 <varlistentry><term>brlock.tdb</term>
305 <listitem><para>byte range locks</para></listitem>
308 <varlistentry><term>browse.dat</term>
309 <listitem><para>browse lists</para></listitem>
312 <varlistentry><term>connections.tdb</term>
313 <listitem><para>share connections (used to enforce max connections, etc...)</para></listitem>
316 <varlistentry><term>gencache.tdb</term>
317 <listitem><para>generic caching db</para></listitem>
320 <varlistentry><term>group_mapping.tdb*</term>
321 <listitem><para>group mapping information</para></listitem>
324 <varlistentry><term>locking.tdb</term>
325 <listitem><para>share modes & oplocks</para></listitem>
328 <varlistentry><term>login_cache.tdb*</term>
329 <listitem><para>bad pw attempts</para></listitem>
332 <varlistentry><term>messages.tdb</term>
333 <listitem><para>Samba messaging system</para></listitem>
336 <varlistentry><term>netsamlogon_cache.tdb*</term>
337 <listitem><para>cache of user net_info_3 struct from net_samlogon() request (as a domain member)</para></listitem>
340 <varlistentry><term>ntdrivers.tdb*</term>
341 <listitem><para>installed printer drivers</para></listitem>
344 <varlistentry><term>ntforms.tdb*</term>
345 <listitem><para>installed printer forms</para></listitem>
348 <varlistentry><term>ntprinters.tdb*</term>
349 <listitem><para>installed printer information</para></listitem>
352 <varlistentry><term>printing/</term>
353 <listitem><para>directory containing tdb per print queue of cached lpq output</para></listitem>
356 <varlistentry><term>registry.tdb</term>
357 <listitem><para>Windows registry skeleton (connect via regedit.exe)</para></listitem>
360 <varlistentry><term>sessionid.tdb</term>
361 <listitem><para>session information (e.g. support for 'utmp = yes')</para></listitem>
364 <varlistentry><term>share_info.tdb*</term>
365 <listitem><para>share acls</para></listitem>
368 <varlistentry><term>winbindd_cache.tdb</term>
369 <listitem><para>winbindd's cache of user lists, etc...</para></listitem>
372 <varlistentry><term>winbindd_idmap.tdb*</term>
373 <listitem><para>winbindd's local idmap db</para></listitem>
376 <varlistentry><term>wins.dat*</term>
377 <listitem><para>wins database when 'wins support = yes'</para></listitem>
385 <title>SIGNALS</title>
387 <para>Sending the <command>smbd</command> a SIGHUP will cause it to
388 reload its <filename>smb.conf</filename> configuration
389 file within a short period of time.</para>
391 <para>To shut down a user's <command>smbd</command> process it is recommended
392 that <command>SIGKILL (-9)</command> <emphasis>NOT</emphasis>
393 be used, except as a last resort, as this may leave the shared
394 memory area in an inconsistent state. The safe way to terminate
395 an <command>smbd</command> is to send it a SIGTERM (-15) signal and wait for
396 it to die on its own.</para>
398 <para>The debug log level of <command>smbd</command> may be raised
399 or lowered using <citerefentry><refentrytitle>smbcontrol</refentrytitle>
400 <manvolnum>1</manvolnum></citerefentry> program (SIGUSR[1|2] signals are no longer
401 used since Samba 2.2). This is to allow transient problems to be diagnosed,
402 whilst still running at a normally low log level.</para>
404 <para>Note that as the signal handlers send a debug write,
405 they are not re-entrant in <command>smbd</command>. This you should wait until
406 <command>smbd</command> is in a state of waiting for an incoming SMB before
407 issuing them. It is possible to make the signal handlers safe
408 by un-blocking the signals before the select call and re-blocking
409 them after, however this would affect performance.</para>
413 <title>SEE ALSO</title>
414 <para><citerefentry><refentrytitle>hosts_access</refentrytitle>
415 <manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>inetd</refentrytitle>
416 <manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>nmbd</refentrytitle>
417 <manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>smb.conf</refentrytitle>
418 <manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>smbclient</refentrytitle>
419 <manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>testparm</refentrytitle>
420 <manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>testprns</refentrytitle>
421 <manvolnum>1</manvolnum></citerefentry>, and the
422 Internet RFC's <filename>rfc1001.txt</filename>, <filename>rfc1002.txt</filename>.
423 In addition the CIFS (formerly SMB) specification is available
424 as a link from the Web page <ulink noescape="1" url="http://samba.org/cifs/">
425 http://samba.org/cifs/</ulink>.</para>
429 <title>AUTHOR</title>
431 <para>The original Samba software and related utilities
432 were created by Andrew Tridgell. Samba is now developed
433 by the Samba Team as an Open Source project similar
434 to the way the Linux kernel is developed.</para>
436 <para>The original Samba man pages were written by Karl Auer.
437 The man page sources were converted to YODL format (another
438 excellent piece of Open Source software, available at <ulink url="ftp://ftp.icce.rug.nl/pub/unix/">
439 ftp://ftp.icce.rug.nl/pub/unix/</ulink>) and updated for the Samba 2.0
440 release by Jeremy Allison. The conversion to DocBook for
441 Samba 2.2 was done by Gerald Carter. The conversion to DocBook XML 4.2 for
442 Samba 3.0 was done by Alexander Bokovoy.</para>