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NSCD(8) FreeBSD System Manager's Manual NSCD(8)
NAME
nscd - name service caching daemon
SYNOPSIS
nscd [-dnst] [-i cachename] [-I cachename]
DESCRIPTION
The nscd utility is the system caching daemon. It can cache almost all
types of data and is basically intended to be used with the nsswitch
subsystem. The cache is actually per-user. This means that each user
can work only with the cached data that were cached by themselves, and
cannot poison the cache of other users. The nscd utility supports two
types of caching:
Type Description
Common caching
Each cached element is the key+value pair. This type of caching
supports policies which are applied when maximum number of cached
elements is exceeded. Three policies are available: FIFO (first in
- first out), LRU (least recently used) and LFU (least frequently
used). This type of caching is used with the getXXXbyname() family
of functions.
Multipart caching
Each cached element is the part of the elements sequence. This
type of caching is intended to be used with the getXXXent() family
of functions.
The nscd utility is able not only to cache elements, but to perform the
actual nsswitch lookups by itself. To enable this feature, use the
perform-actual-lookups parameter in nscd.conf(5).
The nscd utility recognizes the following runtime options:
-n Do not daemonize; nscd will not fork or disconnect itself from
the terminal.
-s Single-threaded mode. Forces using only one thread for all
processing purposes (it overrides the threads parameter in the
nscd.conf(5) file).
-t Trace mode. All trace messages will be written to stdout. This
mode is usually used with -n and -s flags are used for debugging
purposes.
-i cachename
Invalidates personal cache. When specified, nscd acts as the
administration tool. It asks the already running nscd to
invalidate the specified part of the cache of the calling user.
For example, sometimes you may want to invalidate your "hosts"
cache. You can specify "all" as the cachename to invalidate your
personal cache as a whole. You cannot use this option for the
cachename for which the perform-actual-lookups option is enabled.
-I cachename
Invalidates the cache for every user. When specified, nscd acts
SEE ALSO
nsdispatch(3), nscd.conf(5), nsswitch.conf(5)
AUTHORS
Michael Bushkov <bushman@FreeBSD.org>
FreeBSD 14.0-RELEASE-p11 October 5, 2018 FreeBSD 14.0-RELEASE-p11