nscd.conf(5) — Linux manual page


NSCD.CONF(5)            Linux Programmer's Manual           NSCD.CONF(5)

NAME         top

       nscd.conf - name service cache daemon configuration file

DESCRIPTION         top

       The file /etc/nscd.conf is read from nscd(8) at startup.  Each
       line specifies either an attribute and a value, or an attribute,
       service, and a value.  Fields are separated either by SPACE or
       TAB characters.  A '#' (number sign) indicates the beginning of a
       comment; following characters, up to the end of the line, are not
       interpreted by nscd.

       Valid services are passwd, group, hosts, services, or netgroup.

       logfile debug-file-name
              Specifies name of the file to which debug info should be

       debug-level value
              Sets the desired debug level.  The default is 0.

       threads number
              This is the number of threads that are started to wait for
              requests.  At least five threads will always be created.

       max-threads number
              Specifies the maximum number of threads.  The default is

       server-user user
              If this option is set, nscd will run as this user and not
              as root.  If a separate cache for every user is used (-S
              parameter), this option is ignored.

       stat-user user
              Specifies the user who is allowed to request statistics.

       reload-count unlimited | number
              Limit on the number of times a cached entry gets reloaded
              without being used before it gets removed.  The default is

       paranoia <yes|no>
              Enabling paranoia mode causes nscd to restart itself
              periodically.  The default is no.

       restart-interval time
              Sets the restart interval to time seconds if periodic
              restart is enabled by enabling paranoia mode.  The default
              is 3600.

       enable-cache service <yes|no>
              Enables or disables the specified service cache.  The
              default is no.

       positive-time-to-live service value
              Sets the TTL (time-to-live) for positive entries
              (successful queries) in the specified cache for service.
              Value is in seconds.  Larger values increase cache hit
              rates and reduce mean response times, but increase
              problems with cache coherence.

       negative-time-to-live service value
              Sets the TTL (time-to-live) for negative entries
              (unsuccessful queries) in the specified cache for service.
              Value is in seconds.  Can result in significant
              performance improvements if there are several files owned
              by UIDs (user IDs) not in system databases (for example
              untarring the Linux kernel sources as root); should be
              kept small to reduce cache coherency problems.

       suggested-size service value
              This is the internal hash table size, value should remain
              a prime number for optimum efficiency.  The default is

       check-files service <yes|no>
              Enables or disables checking the file belonging to the
              specified service for changes.  The files are /etc/passwd,
              /etc/group, /etc/hosts, /etc/services, and /etc/netgroup.
              The default is yes.

       persistent service <yes|no>
              Keep the content of the cache for service over server
              restarts; useful when paranoia mode is set.  The default
              is no.

       shared service <yes|no>
              The memory mapping of the nscd databases for service is
              shared with the clients so that they can directly search
              in them instead of having to ask the daemon over the
              socket each time a lookup is performed.  The default is

       max-db-size service bytes
              The maximum allowable size, in bytes, of the database
              files for the service.  The default is 33554432.

       auto-propagate service <yes|no>
              When set to no for passwd or group service, then the
              .byname requests are not added to passwd.byuid or
              group.bygid cache.  This can help with tables containing
              multiple records for the same ID.  The default is yes.
              This option is valid only for services passwd and group.

NOTES         top

       The default values stated in this manual page originate from the
       source code of nscd(8) and are used if not overridden in the
       configuration file.  The default values used in the configuration
       file of your distribution might differ.

SEE ALSO         top


COLOPHON         top

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GNU                            2020-12-21                   NSCD.CONF(5)

Pages that refer to this page: nscd(8)