man8/nscd.8

   1 .\" Copyright 1999 SuSE GmbH Nuernberg, Germany
   2 .\" Author: Thorsten Kukuk <kukuk@suse.de>
   3 .\"
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  19 .\"
  20 .\" 2008-12-05 Petr Baudis <pasky@suse.cz>
  21 .\"     Rewrite the NOTES section to reflect modern reality
  22 .\"
  23 .TH NSCD 8 2015-05-07 "GNU" "Linux Programmer's Manual"
  24 .SH NAME
  25 nscd \- name service cache daemon
  26 .SH DESCRIPTION
  27 Nscd is a daemon that provides a cache for the most common name service
  28 requests.
  29 The default configuration file,
  30 .IR /etc/nscd.conf ,
  31 determines the behavior of the cache daemon.
  32 See
  33 .BR nscd.conf (5).
  34
  35 Nscd provides caching for accesses of the
  36 .BR passwd (5),
  37 .BR group (5),
  38 .BR hosts (5)
  39 .BR service (5)
  40 and
  41 .I netgroup
  42 databases through standard libc interfaces, such as
  43 .BR getpwnam (3),
  44 .BR getpwuid (3),
  45 .BR getgrnam (3),
  46 .BR getgrgid (3),
  47 .BR gethostbyname (3),
  48 and others.
  49
  50 There are two caches for each database:
  51 a positive one for items found, and a negative one
  52 for items not found.
  53 Each cache has a separate TTL (time-to-live)
  54 period for its data.
  55 Note that the shadow file is specifically not cached.
  56 .BR getspnam (3)
  57 calls remain uncached as a result.
  58 .SH OPTIONS
  59 .TP
  60 .B "\-\-help"
  61 will give you a list with all options and what they do.
  62 .SH NOTES
  63 The daemon will try to watch for changes in configuration files
  64 appropriate for each database (e.g.,
  65 .I /etc/passwd
  66 for the
  67 .I passwd
  68 database or
  69 .I /etc/hosts
  70 and
  71 .I /etc/resolv.conf
  72 for the
  73 .I hosts
  74 database), and flush the cache when these are changed.
  75 However, this will happen only after a short delay (unless the
  76 .BR inotify (7)
  77 mechanism is available and glibc 2.9 or later is available),
  78 and this auto-detection does not cover configuration files
  79 required by nonstandard NSS modules, if any are specified in
  80 .IR /etc/nsswitch.conf .
  81 In that case, you need to run the following command
  82 after changing the configuration file of the database so that
  83 .B nscd
  84 invalidates its cache:
  85
  86     $ \fBnscd -i\fP \fI<database>\fP
  87 .SH SEE ALSO
  88 .BR nscd.conf (5),
  89 .BR nsswitch.conf (5)
  90 .\" .SH AUTHOR
  91 .\" .B nscd
  92 .\" was written by Thorsten Kukuk and Ulrich Drepper.