LOCKD(NADM) UNIX System V
Name
lockd - Network lock daemon
Syntax
/etc/lockd [ -t timeout ] [ -g graceperiod ] [ -e ]
Description
lockd processes lock requests that are either sent locally
by the kernel or remotely by another lock daemon. lockd
forwards lock requests for remote data to the server site's
lock daemon through the RPC/XDR package. lockd then
requests the status monitor daemon, statd(NADM), for monitor
service. The reply to the lock request will not be sent to
the kernel until the status daemon and the server site's
lock daemon have replied. If either the status monitor or
server site's lock daemon is unavailable, the reply to a
lock request for remote data is delayed until all daemons
become available.
When a server recovers, it waits for a grace period for all
client site lockds to submit reclaim requests. Client site
lockds, on the other hand, are notified by the statd of the
server recovery and promptly resubmit previously granted
lock requests. If a lockd fails to secure a previously
granted lock at the server site, the lockd sends SIGUSR2 to
a process.
lockd should be invoked as early as possible during the
transition from single user to multiuser, so that no other
processes have the opportunity to get a standard System V
lock (See -e option below).
Options
-t timeout
lockd uses timeout (seconds) as the interval
instead of the default value (15 seconds) to
retransmit lock request to the remote server.
-g graceperiod
lockd uses graceperiod (seconds) as the grace
period duration instead of the default value (45
seconds).
-e If there are active locks in the standard system
record locking code, lockd will log a warning to
the console. If the -e option is specified, lockd
will exit immediately if there are active standard
locks. This is so that the administrator has the
option of not effectively destroying a processes'
locks in progress.
See Also
fcntl(S), lockf(S), signal(S), statd(NADM)
(printed 8/17/89) LOCKD(NADM)