lockd: rpc.lockd - network lock daemon
graceperiod] listen_min_backlog] timeout] [nthreads]
The lockd utility is part of the NFS lock manager, which supports
record lock and share lock operations on NFS files. See fcntl(2) and
lockf(2). provides two functions:
· It forwards locking requests for NFS mounted file systems to
the lockd on the NFS server.
· It generates local file locking operations in response to
requests forwarded from running on NFS client machines.
State information kept by the lockd about these locking requests
can be lost if is killed or the operating system is rebooted.
Some of this information can be recovered as follows. When a
server recovers, it waits for a grace period for all NFS client-
site to submit reclaim requests. Client-site is notified by the
of the server recovery, and promptly resubmits previously
granted lock requests. If a fails to secure a previously
granted lock at the server site, then the sends a to the process
holding that lock.
Administrators can make changes to the startup parameters for by
logging in as root and editing the file (see nfs(4)). Adminis‐
trators can also make changes by using the command.
recognizes the following options and command-line arguments:
Deprecated in favor of the
parameter in the NFS default file, which is
equivalent. Specify the number of seconds
that all clients (both NLM and NFSv4) have to
reclaim locks after the server reboots. This
option also controls the NFSv4 lease interval.
The default value is 90 seconds.
Specify the listener backlog,
listen_min_backlog, which is the number of
connect requests that are queued and waiting
to be processed before new connect requests
begin to get dropped.
Specify the number of seconds to wait before retransmitting a
request to the remote server. The default
value is 5 seconds. Equivalent to the parame‐
ter in the NFS default file.
nthreads Specify the maximum number of concurrent
threads that the server can handle. This con‐
currency 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 to the parameter in
the NFS default file.
A directory service that provides service name data base support must
have the following service entries in its database:
Kernel Lock Manager logging can be enabled using By default, the vari‐
able is 0 which disables the Kernel Lock Manager logging feature. The
maximum value is 9. The value determines how detailed the log messages
was developed by Sun Microsystems, Inc. and HP.
SEE ALSOclear_locks(1M), kctune(1M), setoncenv(1M), statd(1M), fcntl(2),
lockf(2), signal(2), getservent(3N), nfs(4), nsswitch.conf(4), ser‐