man8/nscd.8

   1 .\" Copyright 1999 SuSE GmbH Nuernberg, Germany
   2 .\" Author: Thorsten Kukuk <kukuk@suse.de>
   3 .\"
   4 .\" This program is free software; you can redistribute it and/or
   5 .\" modify it under the terms of the GNU General Public License as
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  14 .\" You should have received a copy of the GNU General Public
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  17 .\"
  18 .\" 2008-12-05 Petr Baudis <pasky@suse.cz>
  19 .\"     Rewrite the NOTES section to reflect modern reality
  20 .\"
  21 .TH NSCD 8 2012-05-10 "GNU" "Linux Programmer's Manual"
  22 .SH NAME
  23 nscd \- name service cache daemon
  24 .SH DESCRIPTION
  25 Nscd is a daemon that provides a cache for the most common name service
  26 requests.
  27 The default configuration file,
  28 .IR /etc/nscd.conf ,
  29 determines the behavior of the cache daemon.
  30 See
  31 .BR nscd.conf (5).
  32
  33 Nscd provides caching for accesses of the
  34 .BR passwd (5),
  35 .BR group (5),
  36 and
  37 .BR hosts (5)
  38 databases through standard libc interfaces, such as
  39 .BR getpwnam (3),
  40 .BR getpwuid (3),
  41 .BR getgrnam (3),
  42 .BR getgrgid (3),
  43 .BR gethostbyname (3),
  44 and others.
  45
  46 There are two caches for each database:
  47 a positive one for items found, and a negative one
  48 for items not found.
  49 Each cache has a separate TTL (time-to-live)
  50 period for its data.
  51 Note that the shadow file is specifically not cached.
  52 .BR getspnam (3)
  53 calls remain uncached as a result.
  54 .SH OPTIONS
  55 .TP
  56 .B "\-\-help"
  57 will give you a list with all options and what they do.
  58 .SH NOTES
  59 The daemon will try to watch for changes in configuration files
  60 appropriate for each database (e.g.,
  61 .I /etc/passwd
  62 for the
  63 .I passwd
  64 database or
  65 .I /etc/hosts
  66 and
  67 .I /etc/resolv.conf
  68 for the
  69 .I hosts
  70 database), and flush the cache when these are changed.
  71 However, this will happen only after a short delay (unless the
  72 .BR inotify (7)
  73 mechanism is available and glibc 2.9 or later is available),
  74 and this auto-detection does not cover configuration files
  75 required by nonstandard NSS modules, if any are specified in
  76 .IR /etc/nsswitch.conf .
  77 In that case, you need to run the following command
  78 after changing the configuration file of the database so that
  79 .B nscd
  80 invalidates its cache:
  81
  82     $ \fBnscd -i\fP \fI<database>\fP
  83 .SH SEE ALSO
  84 .BR nscd.conf (5),
  85 .BR nsswitch.conf (5)
  86 .\" .SH AUTHOR
  87 .\" .B nscd
  88 .\" was written by Thorsten Kukuk and Ulrich Drepper.