Section: File Formats (5)Updated: 07 January 2001Local indexUp
NAME
nscd.conf - configuration file for Name Service Caching Daemon
DESCRIPTION
/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:
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.
CACHE OPTIONS
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.
EXAMPLE
# 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