NAME
nis_cachemgr — maintains a cache containing location information about NIS+ servers
SYNOPSIS
/usr/sbin/nis_cachemgr
[ -i ]
[ -n ]
[ -v ]
DESCRIPTION
The
nis_cachemgr
daemon maintains a cache of the NIS+ directory objects.
The cache contains location information necessary to contact the NIS+ servers
that serve the various directories in the name space. This includes transport
addresses, information neeeded to authenticate the server, and a time to live field
which gives a hint on how long the directory object can be cached.
The cache helps to improve the performance of the clients that are traversing
the NIS+ name space.
nis_cachemgr
should be running on all the machines that are using NIS+. However, it is not required that the
nis_cachemgr
program be running in order for NIS+
requests to be serviced.
The cache maintained by this program is shared
by all the processes that access NIS+ on that machine.
The cache is maintained in a file
that is memory mapped (see
mmap
(2))
by all the processes.
On startup,
nis_cachemgr
initializes the cache from the cold start file
(see
nisinit(1M))
and preserves unexpired entries that already exist
in the cache file. Thus, the cache survives machine reboots.
The
nis_cachemgr
program is normally started from a system startup script.
Note:
The
nis_cachemgr
program makes NIS+ requests under the NIS+ principal name of the host
on which it runs. Before running
nis_cachemgr,
security credentials for the host should be added to the
cred.org_dir
table in the host's domain using
nisaddcred(1M).
Credentials of type
DES
will be needed if the NIS+ service is operating at security level 2 (see
rpc.nisd(1M)).
See the
WARNINGS
section, below.
Additionally, a
'keylogin
-r'
needs to be done on the machine.
nisshowcache
can be used to look at the cached objects.
Options
- -i
Force
nis_cachemgr
to ignore the previous cache file and reinitialize
the cache from just the cold start file.
By default, the cache manager initializes itself from both the cold start file
and the old cache file, thereby maintaining the entries in the cache across
machine reboots.
- -n
Run
nis_cachemgr
in an
insecure
mode. By default, before adding a directory object to the shared cache, on the request
of another process on the machine, it checks the encrypted signature on the request
to make sure that the directory object is a valid one and is sent by an authorized
server. In this mode,
nis_cachemgr
adds the directory object to the shared cache without making
this check.
- -v
This flag sets
verbose
mode. In this mode, the
nis_cachemgr
program logs not only errors and warnings,
but also additional status messages.
The additional messages are logged using
syslog(3C)
with a priority of
LOG_INFO.
DIAGNOSTICS
The
nis_cachemgr
daemon logs error messages and warnings using syslog
(see
syslog(3C)).
Error messages are logged to the
DAEMON
facility with a priority of
LOG_ERR,
and warning messages with a priority of
LOG_WARNING.
Additional status messages can be obtained using the
-v
option.
WARNINGS
If the host principal does not have the proper security credentials
in the
cred.org_dir
table for its domain, then running this program without the
'-n'
insecure mode
option may significantly
degrade
the performance of processes issuing NIS+ requests.
FILES
- /var/nis/NIS_SHARED_DIRCACHE
the shared cache file
- /var/nis/NIS_COLD_START
the coldstart file
- /etc/init.d/rpc
initialization scripts for NIS+
AUTHOR
nis_cachemgr
was developed by Sun Microsystems, Inc.
