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">
3 <refentry id="winbindd.8">
6 <refentrytitle>winbindd</refentrytitle>
7 <manvolnum>8</manvolnum>
8 <refmiscinfo class="source">Samba</refmiscinfo>
9 <refmiscinfo class="manual">System Administration tools</refmiscinfo>
10 <refmiscinfo class="version">3.2</refmiscinfo>
15 <refname>winbindd</refname>
16 <refpurpose>Name Service Switch daemon for resolving names
17 from NT servers</refpurpose>
22 <command>winbindd</command>
23 <arg choice="opt">-D</arg>
24 <arg choice="opt">-F</arg>
25 <arg choice="opt">-S</arg>
26 <arg choice="opt">-i</arg>
27 <arg choice="opt">-Y</arg>
28 <arg choice="opt">-d <debug level></arg>
29 <arg choice="opt">-s <smb config file></arg>
30 <arg choice="opt">-n</arg>
35 <title>DESCRIPTION</title>
37 <para>This program is part of the <citerefentry><refentrytitle>samba</refentrytitle>
38 <manvolnum>7</manvolnum></citerefentry> suite.</para>
40 <para><command>winbindd</command> is a daemon that provides
41 a number of services to the Name Service Switch capability found
42 in most modern C libraries, to arbitrary applications via PAM
43 and <command>ntlm_auth</command> and to Samba itself.</para>
45 <para>Even if winbind is not used for nsswitch, it still provides a
46 service to <command>smbd</command>, <command>ntlm_auth</command>
47 and the <command>pam_winbind.so</command> PAM module, by managing connections to
48 domain controllers. In this configuration the
49 <smbconfoption name="idmap uid"/> and <smbconfoption name="idmap gid"/>
50 parameters are not required. (This is known as `netlogon proxy only mode'.)</para>
52 <para>The Name Service Switch allows user
53 and system information to be obtained from different databases
54 services such as NIS or DNS. The exact behaviour can be configured
55 through the <filename>/etc/nsswitch.conf</filename> file.
56 Users and groups are allocated as they are resolved to a range
57 of user and group ids specified by the administrator of the
60 <para>The service provided by <command>winbindd</command> is called `winbind' and
61 can be used to resolve user and group information from a
62 Windows NT server. The service can also provide authentication
63 services via an associated PAM module.</para>
66 The <filename>pam_winbind</filename> module supports the
67 <parameter>auth</parameter>, <parameter>account</parameter>
68 and <parameter>password</parameter> module-types. It should be noted that the
69 <parameter>account</parameter> module simply performs a getpwnam() to verify that
70 the system can obtain a uid for the user, as the domain
71 controller has already performed access control. If the
72 <filename>libnss_winbind</filename> library has been correctly
73 installed, or an alternate source of names configured, this should always succeed.
76 <para>The following nsswitch databases are implemented by
77 the winbindd service: </para>
82 <listitem><para>If specified, this parameter causes
83 the server to operate as a daemon. That is, it detaches
84 itself and runs in the background on the appropriate port.
85 This switch is assumed if <command>winbindd</command> is
86 executed on the command line of a shell.
92 <listitem><para>This feature is only available on IRIX.
93 User information traditionally stored in
94 the <filename>hosts(5)</filename> file and used by
95 <command>gethostbyname(3)</command> functions. Names are
96 resolved through the WINS server or by broadcast.
102 <listitem><para>User information traditionally stored in
103 the <filename>passwd(5)</filename> file and used by
104 <command>getpwent(3)</command> functions. </para></listitem>
109 <listitem><para>Group information traditionally stored in
110 the <filename>group(5)</filename> file and used by
111 <command>getgrent(3)</command> functions. </para></listitem>
115 <para>For example, the following simple configuration in the
116 <filename>/etc/nsswitch.conf</filename> file can be used to initially
117 resolve user and group information from <filename>/etc/passwd
118 </filename> and <filename>/etc/group</filename> and then from the
123 passwd: files winbind
125 ## only available on IRIX: use winbind to resolve hosts:
126 # hosts: files dns winbind
127 ## All other NSS enabled systems should use libnss_wins.so like this:
128 hosts: files dns wins
132 <para>The following simple configuration in the
133 <filename>/etc/nsswitch.conf</filename> file can be used to initially
134 resolve hostnames from <filename>/etc/hosts</filename> and then from the
144 <title>OPTIONS</title>
149 <listitem><para>If specified, this parameter causes
150 the main <command>winbindd</command> process to not daemonize,
151 i.e. double-fork and disassociate with the terminal.
152 Child processes are still created as normal to service
153 each connection request, but the main process does not
154 exit. This operation mode is suitable for running
155 <command>winbindd</command> under process supervisors such
156 as <command>supervise</command> and <command>svscan</command>
157 from Daniel J. Bernstein's <command>daemontools</command>
158 package, or the AIX process monitor.
164 <listitem><para>If specified, this parameter causes
165 <command>winbindd</command> to log to standard output rather
166 than a file.</para></listitem>
169 &stdarg.server.debug;
175 <listitem><para>Tells <command>winbindd</command> to not
176 become a daemon and detach from the current terminal. This
177 option is used by developers when interactive debugging
178 of <command>winbindd</command> is required.
179 <command>winbindd</command> also logs to standard output,
180 as if the <command>-S</command> parameter had been given.
186 <listitem><para>Disable caching. This means winbindd will
187 always have to wait for a response from the domain controller
188 before it can respond to a client and this thus makes things
189 slower. The results will however be more accurate, since
190 results from the cache might not be up-to-date. This
191 might also temporarily hang winbindd if the DC doesn't respond.
197 <listitem><para>Single daemon mode. This means winbindd will run
198 as a single process (the mode of operation in Samba 2.2). Winbindd's
199 default behavior is to launch a child process that is responsible for
200 updating expired cache entries.
209 <title>NAME AND ID RESOLUTION</title>
211 <para>Users and groups on a Windows NT server are assigned
212 a security id (SID) which is globally unique when the
213 user or group is created. To convert the Windows NT user or group
214 into a unix user or group, a mapping between SIDs and unix user
215 and group ids is required. This is one of the jobs that <command>
216 winbindd</command> performs. </para>
218 <para>As winbindd users and groups are resolved from a server, user
219 and group ids are allocated from a specified range. This
220 is done on a first come, first served basis, although all existing
221 users and groups will be mapped as soon as a client performs a user
222 or group enumeration command. The allocated unix ids are stored
223 in a database and will be remembered. </para>
225 <para>WARNING: The SID to unix id database is the only location
226 where the user and group mappings are stored by winbindd. If this
227 store is deleted or corrupted, there is no way for winbindd to
228 determine which user and group ids correspond to Windows NT user
229 and group rids. </para>
231 <para>See the <smbconfoption name="idmap domains"/> or the old <smbconfoption name="idmap backend"/> parameters in
232 <filename>smb.conf</filename> for options for sharing this
233 database, such as via LDAP.</para>
238 <title>CONFIGURATION</title>
240 <para>Configuration of the <command>winbindd</command> daemon
241 is done through configuration parameters in the <citerefentry>
242 <refentrytitle>smb.conf</refentrytitle><manvolnum>5</manvolnum>
243 </citerefentry> file. All parameters should be specified in the
244 [global] section of smb.conf. </para>
248 <smbconfoption name="winbind separator"/></para></listitem>
250 <smbconfoption name="idmap uid"/></para></listitem>
252 <smbconfoption name="idmap gid"/></para></listitem>
254 <smbconfoption name="idmap backend"/></para></listitem>
256 <smbconfoption name="winbind cache time"/></para></listitem>
258 <smbconfoption name="winbind enum users"/></para></listitem>
260 <smbconfoption name="winbind enum groups"/></para></listitem>
262 <smbconfoption name="template homedir"/></para></listitem>
264 <smbconfoption name="template shell"/></para></listitem>
266 <smbconfoption name="winbind use default domain"/></para></listitem>
268 <smbconfoption name="winbind: rpc only"/>
269 Setting this parameter forces winbindd to use RPC
270 instead of LDAP to retrieve information from Domain
278 <title>EXAMPLE SETUP</title>
281 To setup winbindd for user and group lookups plus
282 authentication from a domain controller use something like the
283 following setup. This was tested on an early Red Hat Linux box.
286 <para>In <filename>/etc/nsswitch.conf</filename> put the
289 passwd: files winbind
294 <para>In <filename>/etc/pam.d/*</filename> replace the <parameter>
295 auth</parameter> lines with something like this:
297 auth required /lib/security/pam_securetty.so
298 auth required /lib/security/pam_nologin.so
299 auth sufficient /lib/security/pam_winbind.so
300 auth required /lib/security/pam_unix.so \
301 use_first_pass shadow nullok
306 The PAM module pam_unix has recently replaced the module pam_pwdb.
307 Some Linux systems use the module pam_unix2 in place of pam_unix.
310 <para>Note in particular the use of the <parameter>sufficient
311 </parameter> keyword and the <parameter>use_first_pass</parameter> keyword. </para>
313 <para>Now replace the account lines with this: </para>
315 <para><command>account required /lib/security/pam_winbind.so
318 <para>The next step is to join the domain. To do that use the
319 <command>net</command> program like this: </para>
321 <para><command>net join -S PDC -U Administrator</command></para>
323 <para>The username after the <parameter>-U</parameter> can be any
324 Domain user that has administrator privileges on the machine.
325 Substitute the name or IP of your PDC for "PDC".</para>
327 <para>Next copy <filename>libnss_winbind.so</filename> to
328 <filename>/lib</filename> and <filename>pam_winbind.so
329 </filename> to <filename>/lib/security</filename>. A symbolic link needs to be
330 made from <filename>/lib/libnss_winbind.so</filename> to
331 <filename>/lib/libnss_winbind.so.2</filename>. If you are using an
332 older version of glibc then the target of the link should be
333 <filename>/lib/libnss_winbind.so.1</filename>.</para>
335 <para>Finally, setup a <citerefentry><refentrytitle>smb.conf</refentrytitle>
336 <manvolnum>5</manvolnum></citerefentry> containing directives like the
340 winbind separator = +
341 winbind cache time = 10
342 template shell = /bin/bash
343 template homedir = /home/%D/%U
344 idmap uid = 10000-20000
345 idmap gid = 10000-20000
349 </programlisting></para>
352 <para>Now start winbindd and you should find that your user and
353 group database is expanded to include your NT users and groups,
354 and that you can login to your unix box as a domain user, using
355 the DOMAIN+user syntax for the username. You may wish to use the
356 commands <command>getent passwd</command> and <command>getent group
357 </command> to confirm the correct operation of winbindd.</para>
364 <para>The following notes are useful when configuring and
365 running <command>winbindd</command>: </para>
367 <para><citerefentry><refentrytitle>nmbd</refentrytitle>
368 <manvolnum>8</manvolnum></citerefentry> must be running on the local machine
369 for <command>winbindd</command> to work. </para>
371 <para>PAM is really easy to misconfigure. Make sure you know what
372 you are doing when modifying PAM configuration files. It is possible
373 to set up PAM such that you can no longer log into your system. </para>
375 <para>If more than one UNIX machine is running <command>winbindd</command>,
376 then in general the user and groups ids allocated by winbindd will not
377 be the same. The user and group ids will only be valid for the local
378 machine, unless a shared <smbconfoption name="idmap backend"/> is configured.</para>
380 <para>If the the Windows NT SID to UNIX user and group id mapping
381 file is damaged or destroyed then the mappings will be lost. </para>
386 <title>SIGNALS</title>
388 <para>The following signals can be used to manipulate the
389 <command>winbindd</command> daemon. </para>
394 <listitem><para>Reload the <citerefentry><refentrytitle>smb.conf</refentrytitle>
395 <manvolnum>5</manvolnum></citerefentry> file and
396 apply any parameter changes to the running
397 version of winbindd. This signal also clears any cached
398 user and group information. The list of other domains trusted
399 by winbindd is also reloaded. </para></listitem>
404 <listitem><para>The SIGUSR2 signal will cause <command>
405 winbindd</command> to write status information to the winbind
408 <para>Log files are stored in the filename specified by the
409 log file parameter.</para></listitem>
419 <term><filename>/etc/nsswitch.conf(5)</filename></term>
420 <listitem><para>Name service switch configuration file.</para>
425 <term>/tmp/.winbindd/pipe</term>
426 <listitem><para>The UNIX pipe over which clients communicate with
427 the <command>winbindd</command> program. For security reasons, the
428 winbind client will only attempt to connect to the winbindd daemon
429 if both the <filename>/tmp/.winbindd</filename> directory
430 and <filename>/tmp/.winbindd/pipe</filename> file are owned by
431 root. </para></listitem>
435 <term>$LOCKDIR/winbindd_privileged/pipe</term>
436 <listitem><para>The UNIX pipe over which 'privileged' clients
437 communicate with the <command>winbindd</command> program. For security
438 reasons, access to some winbindd functions - like those needed by
439 the <command>ntlm_auth</command> utility - is restricted. By default,
440 only users in the 'root' group will get this access, however the administrator
441 may change the group permissions on $LOCKDIR/winbindd_privileged to allow
442 programs like 'squid' to use ntlm_auth.
443 Note that the winbind client will only attempt to connect to the winbindd daemon
444 if both the <filename>$LOCKDIR/winbindd_privileged</filename> directory
445 and <filename>$LOCKDIR/winbindd_privileged/pipe</filename> file are owned by
446 root. </para></listitem>
450 <term>/lib/libnss_winbind.so.X</term>
451 <listitem><para>Implementation of name service switch library.
456 <term>$LOCKDIR/winbindd_idmap.tdb</term>
457 <listitem><para>Storage for the Windows NT rid to UNIX user/group
458 id mapping. The lock directory is specified when Samba is initially
459 compiled using the <parameter>--with-lockdir</parameter> option.
460 This directory is by default <filename>/usr/local/samba/var/locks
461 </filename>. </para></listitem>
465 <term>$LOCKDIR/winbindd_cache.tdb</term>
466 <listitem><para>Storage for cached user and group information.
474 <title>VERSION</title>
476 <para>This man page is correct for version 3.0 of
477 the Samba suite.</para>
481 <title>SEE ALSO</title>
483 <para><filename>nsswitch.conf(5)</filename>, <citerefentry>
484 <refentrytitle>samba</refentrytitle>
485 <manvolnum>7</manvolnum></citerefentry>, <citerefentry>
486 <refentrytitle>wbinfo</refentrytitle>
487 <manvolnum>1</manvolnum></citerefentry>, <citerefentry>
488 <refentrytitle>ntlm_auth</refentrytitle>
489 <manvolnum>8</manvolnum></citerefentry>, <citerefentry>
490 <refentrytitle>smb.conf</refentrytitle>
491 <manvolnum>5</manvolnum></citerefentry>, <citerefentry>
492 <refentrytitle>pam_winbind</refentrytitle>
493 <manvolnum>8</manvolnum></citerefentry></para>
497 <title>AUTHOR</title>
499 <para>The original Samba software and related utilities
500 were created by Andrew Tridgell. Samba is now developed
501 by the Samba Team as an Open Source project similar
502 to the way the Linux kernel is developed.</para>
504 <para><command>wbinfo</command> and <command>winbindd</command> were
505 written by Tim Potter.</para>
507 <para>The conversion to DocBook for Samba 2.2 was done
508 by Gerald Carter. The conversion to DocBook XML 4.2 for
509 Samba 3.0 was done by Alexander Bokovoy.</para>