path: root/man5/nscd.conf.5

.\" Copyright (c) 1999, 2000 SuSE GmbH Nuernberg, Germany
.\" Author: Thorsten Kukuk <kukuk@suse.de>
.\"
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.TH NSCD.CONF 5 2020-12-21 "GNU" "Linux Programmer's Manual"
.SH NAME
nscd.conf \- name service cache daemon configuration file
.SH DESCRIPTION
The file
.I /etc/nscd.conf
is read from
.BR 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 \(aq#\(aq (number sign) indicates the beginning of a
comment; following characters, up to the end of the line,
are not interpreted by nscd.
.PP
Valid services are \fIpasswd\fP, \fIgroup\fP, \fIhosts\fP, \fIservices\fP,
or \fInetgroup\fP.
.PP
.B logfile
.I debug-file-name
.RS
Specifies name of the file to which debug info should be written.
.RE
.PP
.B debug\-level
.I value
.RS
Sets the desired debug level.
The default is 0.
.RE
.PP
.B threads
.I number
.RS
This is the number of threads that are started to wait for
requests.
At least five threads will always be created.
.RE
.PP
.B max\-threads
.I number
.RS
Specifies the maximum number of threads.
The default is 32.
.RE
.PP
.B server\-user
.I user
.RS
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.
.RE
.PP
.B stat\-user
.I user
.RS
Specifies the user who is allowed to request statistics.
.RE
.PP
.B reload\-count
unlimited |
.I number
.RS
Limit on the number of times a cached entry gets reloaded without being used
before it gets removed.
The default is 5.
.RE
.PP
.B paranoia
.I <yes|no>
.RS
Enabling paranoia mode causes nscd to restart itself periodically.
The default is no.
.RE
.PP
.B restart\-interval
.I time
.RS
Sets the restart interval to
.I time
seconds
if periodic restart is enabled by enabling
.B paranoia
mode.
The default is 3600.
.RE
.PP
.B enable\-cache
.I service
.I <yes|no>
.RS
Enables or disables the specified
.I service
cache.
The default is no.
.RE
.PP
.B positive\-time\-to\-live
.I service
.I value
.RS
Sets the TTL (time-to-live) for positive entries (successful queries)
in the specified cache for
.IR service .
.I Value
is in seconds.
Larger values increase cache hit rates and reduce mean
response times, but increase problems with cache coherence.
.RE
.PP
.B negative\-time\-to\-live
.I service
.I value
.RS
Sets the TTL (time-to-live) for negative entries (unsuccessful queries)
in the specified cache for
.IR service .
.I 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.
.RE
.PP
.B suggested\-size
.I service
.I value
.RS
This is the internal hash table size,
.I value
should remain a prime number for optimum efficiency.
The default is 211.
.RE
.PP
.B check\-files
.I service
.I <yes|no>
.RS
Enables or disables checking the file belonging to the specified
.I service
for changes.
The files are
.IR /etc/passwd ,
.IR /etc/group ,
.IR /etc/hosts ,
.IR /etc/services ,
and
.IR /etc/netgroup .
The default is yes.
.RE
.PP
.B persistent
.I service
.I <yes|no>
.RS
Keep the content of the cache for
.I service
over server restarts; useful when
.B paranoia
mode is set.
The default is no.
.RE
.PP
.B shared
.I service
.I <yes|no>
.RS
The memory mapping of the nscd databases for
.I 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 no.
.RE
.PP
.B max\-db\-size
.I service
.I bytes
.RS
The maximum allowable size, in bytes, of the database files for the
.IR service .
The default is 33554432.
.RE
.PP
.B auto\-propagate
.I service
.I <yes|no>
.RS
When set to
.I no
for
.I passwd
or
.I group
service, then the
.I .byname
requests are not added to
.I passwd.byuid
or
.I 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
.I passwd
and
.IR group .
.RE
.SH NOTES
The default values stated in this manual page originate
from the source code of
.BR 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.
.SH SEE ALSO
.BR nscd (8)
.\" .SH AUTHOR
.\" .B nscd
.\" was written by Thorsten Kukuk and Ulrich Drepper.
.SH COLOPHON
This page is part of release 5.10 of the Linux
.I 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/.