nscd(8) — Linux manual page

NSCD(8)                 Linux Programmer's Manual                NSCD(8)

NAME         top

       nscd - name service cache daemon

DESCRIPTION         top

       nscd is a daemon that provides a cache for the most common name
       service requests.  The default configuration file,
       /etc/nscd.conf, determines the behavior of the cache daemon.  See
       nscd.conf(5).

       nscd provides caching for accesses of the passwd(5), group(5),
       hosts(5) services(5) and netgroup databases through standard libc
       interfaces, such as getpwnam(3), getpwuid(3), getgrnam(3),
       getgrgid(3), gethostbyname(3), and others.

       There are two caches for each database: a positive one for items
       found, and a negative one for items not found.  Each cache has a
       separate TTL (time-to-live) period for its data.  Note that the
       shadow file is specifically not cached.  getspnam(3) calls remain
       uncached as a result.

OPTIONS         top

       --help will give you a list with all options and what they do.

NOTES         top

       The daemon will try to watch for changes in configuration files
       appropriate for each database (e.g., /etc/passwd for the passwd
       database or /etc/hosts and /etc/resolv.conf for the hosts
       database), and flush the cache when these are changed.  However,
       this will happen only after a short delay (unless the inotify(7)
       mechanism is available and glibc 2.9 or later is available), and
       this auto-detection does not cover configuration files required
       by nonstandard NSS modules, if any are specified in
       /etc/nsswitch.conf.  In that case, you need to run the following
       command after changing the configuration file of the database so
       that nscd invalidates its cache:

           $ nscd -i <database>

SEE ALSO         top

       nscd.conf(5), nsswitch.conf(5)

COLOPHON         top

       This page is part of release 5.13 of the Linux man-pages project.
       A description of the project, information about reporting bugs,
       and the latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.

GNU                            2015-05-07                        NSCD(8)

Pages that refer to this page: nscd.conf(5)

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