lockd(1M)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | ATTRIBUTES | SEE ALSO

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:

• It forwards fcntl(2) locking requests for NFS mounted file systems to the lock manager on the NFS server.

• 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 daemon, 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 wanting to change startup parameters for lockd should, as root, make changes in the /etc/default/nfs file rather than editing the /etc/init.d/nfs.client file. See nfs(4).

OPTIONS

The following options are supported:

-g graceperiod

Specify the number of seconds that clients have to reclaim locks after the server reboots. The default is 45 seconds. Equivalent of the LOCKD_GRACE_PERIOD parameter in the nfs file.

-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

statd(1M), fcntl(2), lockf(3C), nfs(4), attributes(5)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | ATTRIBUTES | SEE ALSO