RPC.LOCKD(8) BSD System Manager's Manual RPC.LOCKD(8)NAMErpc.lockd — NFS file locking daemon
SYNOPSISrpc.lockd [-d debug_level] [-g grace_period]
[-x host_monitor_cache_period]
DESCRIPTION
The rpc.lockd utility provides monitored and unmonitored file and record
locking services in an NFS environment. To monitor the status of hosts
requesting locks, the locking daemon typically operates in conjunction
with rpc.statd(8).
The rpc.lockd utility runs whenever its services are needed to support
either the NFS server (see nfsd(8)) or the NFS client (an NFS file system
on which file locking requests have been made). The daemon will remain
running until a short time after its services are no longer needed to
support either the NFS client or NFS server. rpc.lockd will also make
sure that the statd service (on which it depends) is running.
The following is a list of command line options that are available. How‐
ever, since rpc.lockd is normally started by launchd(8), configuration of
these options should be controlled using the equivalent settings in the
NFS configuration file. See nfs.conf(5) for a list of tunable parame‐
ters.
-d The -d option causes debugging information to be written to sys‐
log, recording all RPC transactions to the daemon. These mes‐
sages are logged with level LOG_DEBUG and facility LOG_DAEMON.
Specifying a debug_level of 1 results in the generation of one
log line per protocol operation. Higher debug levels can be
specified, causing display of operation arguments and internal
operations of the daemon.
-g The -g option allows to specify the grace period (in seconds).
During the grace period rpc.lockd only accepts requests from
hosts which are reinitialising locks which existed before the
server restart. Default is 45 seconds.
-x The -x option tells rpc.lockd how long to cache state records for
monitored hosts. Setting it to zero will disable the cache which
will make lock and unlock requests from a single client more
expensive because of additional interaction with the client's
statd. The default cache time is 60 seconds.
Error conditions are logged to syslog, irrespective of the debug level,
using log level LOG_ERR and facility LOG_DAEMON.
FILES
/var/run/lockd.pid The pid of the current lockd daemon.
/System/Library/LaunchDaemons/com.apple.lockd.plist
The lockd service's property list file
for launchd(8).
/usr/include/rpcsvc/nlm_prot.x RPC protocol specification for the net‐
work lock manager protocol.
SEE ALSOnfs.conf(5), rpc.statd(8), syslog(3), launchd(8)BUGS
The current implementation serialises locks requests that could be
shared.
STANDARDS
The implementation is based on the specification in "Protocols for X/Open
PC Interworking: XNFS, Issue 4", X/Open CAE Specification C218, ISBN 1
872630 66 9.
HISTORY
A version of rpc.lockd appeared in SunOS 4.
BSD January 9, 2007 BSD
