nscd.conf - configuration file for Name Service Caching Daemon


   /etc/nscd.conf  configures  the  caches used by nscd(8) as well as some
   generic options.  nscd(8) is able to use  a  configuration  file  at  a
   different  location, when supplied with the -f or --config-file command
   line option.

   The configuration file consists of a set of lines.   Empty  lines,  and
   text after a '#' is ignored.  All remaining lines denote the setting of
   an option.  White space before and after options, and  between  options
   and option arguments is ignored.

   There  are  two  kinds  of options: General options influence nscd(8)'s
   general  behaviour,  while  cache  related  options  only  affect   the
   specified cache. Options are set like this:

     general_option option
     cache_option cache_name option


   logfile file
          Specifies the name of the debug log-file that nscd(8) should use
          if debug-level is higher than 0.  If this  option  is  not  set,
          nscd(8) will write its debug output to stderr.

   debug-level level
          If  level  is  higher  than  0,  nscd(8)  will create some debug
          output. The higher the level, the more verbose the output.

   threads #threads
          This option sets the number of threads that nscd(8)  should  use
          by  default. It can be overridden by calling nscd(8) with the -t
          or --nthreads argument. If neither this configuration option nor
          the  command  line  argument is given, nscd(8) uses 5 threads by
          default. The minimum is 3. More threads means more  simultaneous
          connections that nscd(8) can handle.

   max-threads #threads
          Specifies the maximum number of threads to be started.

   server-user user
          By  default, nscd(8) is run as user root. This option can be set
          to force nscd(8) to  drop  root  privileges  after  startup.  It
          cannot  be  used  when nscd(8) is called with the -S or --secure
          argument. Also note that some services require that nscd run  as
          root, so using this may break those lookup services.

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

   paranoia bool
          bool  must  be  one of yes or no.  Enabling paranoia mode causes
          nscd(8) to restart itself periodically.

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


   All cache options take two arguments. The first one denotes the service
   or cache the option should affect. Currently  service  can  be  one  of
   passwd, group, or hosts.

   enable-cache service bool
          bool  must  be  one  of  yes  or  no.  Each cache is disabled by
          default and must be enabled explicitly by setting  this  options
          to yes.

   positive-time-to-live service secs
          This  is  the  number  of  seconds after which a cached entry is
          removed from the cache. This defaults to  3600  seconds  (i.  e.
          one hour).

   negative-time-to-live service secs
          If an entry is not found by the Name Service, it is added to the
          cache and marked as "not existent". This option sets the  number
          of seconds after which such a not existent entry is removed from
          the cache. This defaults to 20 seconds for the password and host
          caches and to 60 seconds for the group cache.

   suggested-size service prime-number
          This  option sets the size of the hash that is used to store the
          cache entries. As this is a hash, it should be reasonably larger
          than the maximum number of entries that is expected to be cached
          simultaneously and should be a prime number. It  defaults  to  a
          size of 211 entries.

   check-files service bool
          bool  must  be  one of yes (default) or no.  If file checking is
          enabled, nscd(8) periodically checks the  modification  time  of
          /etc/passwd,  /etc/group,  or /etc/hosts (for the passwd, group,
          and host cache respectively) and invalidates the  cache  if  the
          file has changed since the last check.

   persistent service bool
          bool  must  be  one of yes (default) or no.  Keep the content of
          the  cache  for  service  over  nscd(8)  restarts.  Useful  when
          paranoia mode is set.

   shared service bool
          bool  must be one of yes (default) or no.  The memory mapping of
          the nscd(8) 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.

   reload-count #number
          Sets the number of times a cached record is reloaded  before  it
          is  pruned from the cache. Each cache record has a timeout, when
          that timeout expires, nscd(8) will either reload it  (query  the
          NSS service again if the data hasn't changed), or drop it.

   max-db-size service number-of-bytes
          Sets the maximum allowable size for the service.

   auto-propagate service bool
          When  set  to  no  for passwd or group service, then the .byname
          requests are not added to  passwd.byuid  or  group.bygid  cache.
          This  may  help  for  tables containing multiple records for the
          same id.


   # This is a comment.

       logfile                 /var/log/nscd.log
       threads                 6
       server-user             nobody
       debug-level             0

       enable-cache            passwd          yes
       positive-time-to-live   passwd          600
       negative-time-to-live   passwd          20
       suggested-size          passwd          211
       check-files             passwd          yes

       enable-cache            group           yes
       positive-time-to-live   group           3600
       negative-time-to-live   group           60
       suggested-size          group           211
       check-files             group           yes

       enable-cache            hosts           yes
       positive-time-to-live   hosts           3600
       negative-time-to-live   hosts           20
       suggested-size          hosts           211
       check-files             hosts           yes


   nscd(8), nsswitch.conf(5)


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