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lockd(8c) [ultrix man page]

lockd(8c)																 lockd(8c)

Name
       lockd - network lock daemon

Syntax
       /usr/etc/lockd [ -t timeout ] [ -g graceperiod ]

Description
       The  daemon processes lock requests that are either sent locally by the kernel or remotely by another lock daemon.  The NFS locking service
       makes this advisory locking support possible by using the system call and the subroutine.  The daemon forwards  lock  requests  for  remote
       data  to  the  server  site's lock daemon.  The daemon then requests the status monitor daemon, for monitor service.  The reply to the lock
       request is not 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 daemons to submit reclaim requests.  Client site daemons are noti-
       fied by of the server recovery and promptly resubmit previously granted lock requests.  If a client site's daemon fails	to  secure  previ-
       ously  granted  locks  at  the server site, the daemon sends the signal SIGLOST to all the processes that were previously holding locks and
       cannot reclaim them.

Options
       -t timeout      The daemon uses timeout (in seconds) as the interval instead of the default value  of  15  seconds  to  retransmit  a  lock
		       request to the remote server.

       -g graceperiod  The daemon uses graceperiod (in seconds) as the grace period duration instead of the default value of 45 seconds.

See Also
       fcntl(2), lockf(3), signal(3), statd(8c)

																	 lockd(8c)

Check Out this Related Man Page

lockd(1M)						  System Administration Commands						 lockd(1M)

NAME
lockd - network lock daemon SYNOPSIS
/usr/lib/nfs/lockd [-g graceperiod] [-l listen_min_backlog] [-t timeout] [nthreads] DESCRIPTION
The lockd utility is part of the NFS lock manager, which supports record locking operations on NFS files. See fcntl(2) and lockf(3C). The lock manager provides the following two functions: o It forwards fcntl(2) locking requests for NFS mounted file systems to the lock manager on the NFS server. o It generates local file locking operations in response to requests forwarded from lock managers running on NFS client machines. State information kept by the lock manager about these locking requests can be lost if the lockd is killed or the operating system is rebooted. Some of this information can be recovered as follows. When the server lock manager restarts, it waits for a grace period for all client-site lock managers to submit reclaim requests. Client-site lock managers, on the other hand, are notified by the status monitor dae- mon, statd(1M), of the restart and promptly resubmit previously granted lock requests. If the lock daemon fails to secure a previously granted lock at the server site, then it sends SIGLOST to a process. Administrators can make changes to the startup parameters for lockd by logging in as root and editing the /etc/default/nfs file (See nfs(4)). OPTIONS
The following options are supported: -g graceperiod Deprecated in favor of GRACE_PERIOD. Specify the number of seconds that all clients (both NLM and NFSv4) have to reclaim locks after the server reboots. It also controls the NFSv4 lease interval. This option is equivalent to the LOCKD_GRACE_PERIOD parameter. -l listen_min_backlog Specify the listener backlog (listen_min_backlog). listen_min_backlog is the number connect requests that are queued and waiting to be processed before new connect requests start to get dropped. -t timeout Specify the number of seconds to wait before retransmitting a lock request to the remote server. The default value is 15 seconds. Equivalent of the LOCKD_RETRANSMIT_TIMEOUT parameter in the nfs file. OPERANDS
nthreads Specify the maximum number of concurrent threads that the server can handle. This concurrency is achieved by up to nthreads threads created as needed in the kernel. nthreads should be based on the load expected on this server. If nthreads is not specified, the maximum number of concurrent threads will default to 20. Equivalent of the LOCKD_SERVERS parameter in the nfs file. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWnfscu | +-----------------------------+-----------------------------+ SEE ALSO
svcs(1), automountd(1M), clear_locks(1M), mount_nfs(1M), share(1M), share_nfs(1M), statd(1M), svcadm(1M), fcntl(2), lockf(3C), nfs(4), attributes(5), smf(5) NOTES
The lockd service is managed by the service management facility, smf(5), under the service identifier: svc:/network/nfs/nlockmgr Administrative actions on this service, such as enabling, disabling, or requesting restart, can be performed using svcadm(1M). The ser- vice's status can be queried using the svcs(1) command. If it is disabled, it will be enabled by mount_nfs(1M), share_nfs(1M), and automountd(1M) unless its application/auto_enable prop- erty is set to false. This daemon might not exist in a future release of Solaris. SunOS 5.10 17 Nov 2004 lockd(1M)
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