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 configuraiton the
49 <smbconfoption name="idmap uid"/> and
50 <smbconfoption name="idmap gid"/>
51 parameters are not required. (This is known as `netlogon proxy only mode'.)</para>
53 <para> The Name Service Switch allows user
54 and system information to be obtained from different databases
55 services such as NIS or DNS. The exact behaviour can be configured
56 throught the <filename>/etc/nsswitch.conf</filename> file.
57 Users and groups are allocated as they are resolved to a range
58 of user and group ids specified by the administrator of the
61 <para>The service provided by <command>winbindd</command> is called `winbind' and
62 can be used to resolve user and group information from a
63 Windows NT server. The service can also provide authentication
64 services via an associated PAM module. </para>
67 The <filename>pam_winbind</filename> module supports the
68 <parameter>auth</parameter>, <parameter>account</parameter>
69 and <parameter>password</parameter>
70 module-types. It should be noted that the
71 <parameter>account</parameter> module simply performs a getpwnam() to verify that
72 the system can obtain a uid for the user, as the domain
73 controller has already performed access control. If the
74 <filename>libnss_winbind</filename> library has been correctly
75 installed, or an alternate source of names configured, this should always succeed.
78 <para>The following nsswitch databases are implemented by
79 the winbindd service: </para>
84 <listitem><para>If specified, this parameter causes
85 the server to operate as a daemon. That is, it detaches
86 itself and runs in the background on the appropriate port.
87 This switch is assumed if <command>winbindd</command> is
88 executed on the command line of a shell.
94 <listitem><para>This feature is only available on IRIX.
95 User information traditionally stored in
96 the <filename>hosts(5)</filename> file and used by
97 <command>gethostbyname(3)</command> functions. Names are
98 resolved through the WINS server or by broadcast.
104 <listitem><para>User information traditionally stored in
105 the <filename>passwd(5)</filename> file and used by
106 <command>getpwent(3)</command> functions. </para></listitem>
111 <listitem><para>Group information traditionally stored in
112 the <filename>group(5)</filename> file and used by
113 <command>getgrent(3)</command> functions. </para></listitem>
117 <para>For example, the following simple configuration in the
118 <filename>/etc/nsswitch.conf</filename> file can be used to initially
119 resolve user and group information from <filename>/etc/passwd
120 </filename> and <filename>/etc/group</filename> and then from the
125 passwd: files winbind
127 ## only available on IRIX: use winbind to resolve hosts:
128 # hosts: files dns winbind
129 ## All other NSS enabled systems should use libnss_wins.so like this:
130 hosts: files dns wins
134 <para>The following simple configuration in the
135 <filename>/etc/nsswitch.conf</filename> file can be used to initially
136 resolve hostnames from <filename>/etc/hosts</filename> and then from the
146 <title>OPTIONS</title>
151 <listitem><para>If specified, this parameter causes
152 the main <command>winbindd</command> process to not daemonize,
153 i.e. double-fork and disassociate with the terminal.
154 Child processes are still created as normal to service
155 each connection request, but the main process does not
156 exit. This operation mode is suitable for running
157 <command>winbindd</command> under process supervisors such
158 as <command>supervise</command> and <command>svscan</command>
159 from Daniel J. Bernstein's <command>daemontools</command>
160 package, or the AIX process monitor.
166 <listitem><para>If specified, this parameter causes
167 <command>winbindd</command> to log to standard output rather
168 than a file.</para></listitem>
171 &stdarg.server.debug;
177 <listitem><para>Tells <command>winbindd</command> to not
178 become a daemon and detach from the current terminal. This
179 option is used by developers when interactive debugging
180 of <command>winbindd</command> is required.
181 <command>winbindd</command> also logs to standard output,
182 as if the <command>-S</command> parameter had been given.
188 <listitem><para>Disable caching. This means winbindd will
189 always have to wait for a response from the domain controller
190 before it can respond to a client and this thus makes things
191 slower. The results will however be more accurate, since
192 results from the cache might not be up-to-date. This
193 might also temporarily hang winbindd if the DC doesn't respond.
199 <listitem><para>Single daemon mode. This means winbindd will run
200 as a single process (the mode of operation in Samba 2.2). Winbindd's
201 default behavior is to launch a child process that is responsible for
202 updating expired cache entries.
211 <title>NAME AND ID RESOLUTION</title>
213 <para>Users and groups on a Windows NT server are assigned
214 a security id (SID) which is globally unique when the
215 user or group is created. To convert the Windows NT user or group
216 into a unix user or group, a mapping between SIDs and unix user
217 and group ids is required. This is one of the jobs that <command>
218 winbindd</command> performs. </para>
220 <para>As winbindd users and groups are resolved from a server, user
221 and group ids are allocated from a specified range. This
222 is done on a first come, first served basis, although all existing
223 users and groups will be mapped as soon as a client performs a user
224 or group enumeration command. The allocated unix ids are stored
225 in a database and will be remembered. </para>
227 <para>WARNING: The SID to unix id database is the only location
228 where the user and group mappings are stored by winbindd. If this
229 store is deleted or corrupted, there is no way for winbindd to
230 determine which user and group ids correspond to Windows NT user
231 and group rids. </para>
233 <para>See the <smbconfoption name="idmap domains"/> or the old <smbconfoption name="idmap backend"/> parameters in
234 <filename>smb.conf</filename> for options for sharing this
235 database, such as via LDAP.</para>
240 <title>CONFIGURATION</title>
242 <para>Configuration of the <command>winbindd</command> daemon
243 is done through configuration parameters in the <citerefentry>
244 <refentrytitle>smb.conf</refentrytitle><manvolnum>5</manvolnum>
245 </citerefentry> file. All parameters should be specified in the
246 [global] section of smb.conf. </para>
250 <smbconfoption name="winbind separator"/></para></listitem>
252 <smbconfoption name="idmap uid"/></para></listitem>
254 <smbconfoption name="idmap gid"/></para></listitem>
256 <smbconfoption name="idmap backend"/></para></listitem>
258 <smbconfoption name="winbind cache time"/></para></listitem>
260 <smbconfoption name="winbind enum users"/></para></listitem>
262 <smbconfoption name="winbind enum groups"/></para></listitem>
264 <smbconfoption name="template homedir"/></para></listitem>
266 <smbconfoption name="template shell"/></para></listitem>
268 <smbconfoption name="winbind use default domain"/></para></listitem>
270 <smbconfoption name="winbind: rpc only"/>
271 Setting this parameter forces winbindd to use RPC
272 instead of LDAP to retrieve information from Domain
280 <title>EXAMPLE SETUP</title>
283 To setup winbindd for user and group lookups plus
284 authentication from a domain controller use something like the
285 following setup. This was tested on an early Red Hat Linux box.
288 <para>In <filename>/etc/nsswitch.conf</filename> put the
291 passwd: files winbind
296 <para>In <filename>/etc/pam.d/*</filename> replace the <parameter>
297 auth</parameter> lines with something like this:
299 auth required /lib/security/pam_securetty.so
300 auth required /lib/security/pam_nologin.so
301 auth sufficient /lib/security/pam_winbind.so
302 auth required /lib/security/pam_unix.so \
303 use_first_pass shadow nullok
308 The PAM module pam_unix has recently replaced the module pam_pwdb.
309 Some Linux systems use the module pam_unix2 in place of pam_unix.
312 <para>Note in particular the use of the <parameter>sufficient
313 </parameter> keyword and the <parameter>use_first_pass</parameter> keyword. </para>
315 <para>Now replace the account lines with this: </para>
317 <para><command>account required /lib/security/pam_winbind.so
320 <para>The next step is to join the domain. To do that use the
321 <command>net</command> program like this: </para>
323 <para><command>net join -S PDC -U Administrator</command></para>
325 <para>The username after the <parameter>-U</parameter> can be any
326 Domain user that has administrator privileges on the machine.
327 Substitute the name or IP of your PDC for "PDC".</para>
329 <para>Next copy <filename>libnss_winbind.so</filename> to
330 <filename>/lib</filename> and <filename>pam_winbind.so
331 </filename> to <filename>/lib/security</filename>. A symbolic link needs to be
332 made from <filename>/lib/libnss_winbind.so</filename> to
333 <filename>/lib/libnss_winbind.so.2</filename>. If you are using an
334 older version of glibc then the target of the link should be
335 <filename>/lib/libnss_winbind.so.1</filename>.</para>
337 <para>Finally, setup a <citerefentry><refentrytitle>smb.conf</refentrytitle>
338 <manvolnum>5</manvolnum></citerefentry> containing directives like the
342 winbind separator = +
343 winbind cache time = 10
344 template shell = /bin/bash
345 template homedir = /home/%D/%U
346 idmap uid = 10000-20000
347 idmap gid = 10000-20000
351 </programlisting></para>
354 <para>Now start winbindd and you should find that your user and
355 group database is expanded to include your NT users and groups,
356 and that you can login to your unix box as a domain user, using
357 the DOMAIN+user syntax for the username. You may wish to use the
358 commands <command>getent passwd</command> and <command>getent group
359 </command> to confirm the correct operation of winbindd.</para>
366 <para>The following notes are useful when configuring and
367 running <command>winbindd</command>: </para>
369 <para><citerefentry><refentrytitle>nmbd</refentrytitle>
370 <manvolnum>8</manvolnum></citerefentry> must be running on the local machine
371 for <command>winbindd</command> to work. </para>
373 <para>PAM is really easy to misconfigure. Make sure you know what
374 you are doing when modifying PAM configuration files. It is possible
375 to set up PAM such that you can no longer log into your system. </para>
377 <para>If more than one UNIX machine is running <command>winbindd</command>,
378 then in general the user and groups ids allocated by winbindd will not
379 be the same. The user and group ids will only be valid for the local
380 machine, unless a shared <smbconfoption name="idmap backend"/> is configured.</para>
382 <para>If the the Windows NT SID to UNIX user and group id mapping
383 file is damaged or destroyed then the mappings will be lost. </para>
388 <title>SIGNALS</title>
390 <para>The following signals can be used to manipulate the
391 <command>winbindd</command> daemon. </para>
396 <listitem><para>Reload the <citerefentry><refentrytitle>smb.conf</refentrytitle>
397 <manvolnum>5</manvolnum></citerefentry> file and
398 apply any parameter changes to the running
399 version of winbindd. This signal also clears any cached
400 user and group information. The list of other domains trusted
401 by winbindd is also reloaded. </para></listitem>
406 <listitem><para>The SIGUSR2 signal will cause <command>
407 winbindd</command> to write status information to the winbind
410 <para>Log files are stored in the filename specified by the
411 log file parameter.</para></listitem>
421 <term><filename>/etc/nsswitch.conf(5)</filename></term>
422 <listitem><para>Name service switch configuration file.</para>
427 <term>/tmp/.winbindd/pipe</term>
428 <listitem><para>The UNIX pipe over which clients communicate with
429 the <command>winbindd</command> program. For security reasons, the
430 winbind client will only attempt to connect to the winbindd daemon
431 if both the <filename>/tmp/.winbindd</filename> directory
432 and <filename>/tmp/.winbindd/pipe</filename> file are owned by
433 root. </para></listitem>
437 <term>$LOCKDIR/winbindd_privileged/pipe</term>
438 <listitem><para>The UNIX pipe over which 'privileged' clients
439 communicate with the <command>winbindd</command> program. For security
440 reasons, access to some winbindd functions - like those needed by
441 the <command>ntlm_auth</command> utility - is restricted. By default,
442 only users in the 'root' group will get this access, however the administrator
443 may change the group permissions on $LOCKDIR/winbindd_privileged to allow
444 programs like 'squid' to use ntlm_auth.
445 Note that the winbind client will only attempt to connect to the winbindd daemon
446 if both the <filename>$LOCKDIR/winbindd_privileged</filename> directory
447 and <filename>$LOCKDIR/winbindd_privileged/pipe</filename> file are owned by
448 root. </para></listitem>
452 <term>/lib/libnss_winbind.so.X</term>
453 <listitem><para>Implementation of name service switch library.
458 <term>$LOCKDIR/winbindd_idmap.tdb</term>
459 <listitem><para>Storage for the Windows NT rid to UNIX user/group
460 id mapping. The lock directory is specified when Samba is initially
461 compiled using the <parameter>--with-lockdir</parameter> option.
462 This directory is by default <filename>/usr/local/samba/var/locks
463 </filename>. </para></listitem>
467 <term>$LOCKDIR/winbindd_cache.tdb</term>
468 <listitem><para>Storage for cached user and group information.
476 <title>VERSION</title>
478 <para>This man page is correct for version 3 of
479 the Samba suite.</para>
483 <title>SEE ALSO</title>
485 <para><filename>nsswitch.conf(5)</filename>, <citerefentry>
486 <refentrytitle>samba</refentrytitle>
487 <manvolnum>7</manvolnum></citerefentry>, <citerefentry>
488 <refentrytitle>wbinfo</refentrytitle>
489 <manvolnum>1</manvolnum></citerefentry>, <citerefentry>
490 <refentrytitle>ntlm_auth</refentrytitle>
491 <manvolnum>8</manvolnum></citerefentry>, <citerefentry>
492 <refentrytitle>smb.conf</refentrytitle>
493 <manvolnum>5</manvolnum></citerefentry>, <citerefentry>
494 <refentrytitle>pam_winbind</refentrytitle>
495 <manvolnum>8</manvolnum></citerefentry></para>
499 <title>AUTHOR</title>
501 <para>The original Samba software and related utilities
502 were created by Andrew Tridgell. Samba is now developed
503 by the Samba Team as an Open Source project similar
504 to the way the Linux kernel is developed.</para>
506 <para><command>wbinfo</command> and <command>winbindd</command> were
507 written by Tim Potter.</para>
509 <para>The conversion to DocBook for Samba 2.2 was done
510 by Gerald Carter. The conversion to DocBook XML 4.2 for
511 Samba 3.0 was done by Alexander Bokovoy.</para>