Manual Pages for UNIX Operating System command usage for man lockd

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  fol-
     lowing 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 lock-
     ing  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 res-
     tarts, 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 mon-
     itor 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 can make changes to  the  startup  parameters
     for  lockd  by logging in as root and using the sharectl(1M)
     command.

  SMF Management
     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 service's status can be  queried  using  the



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System Administration Commands                          lockd(1M)



     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 property is set to false.


     The sharectl(1M) command is used to manipulate  the  startup
     SMF parameters for lockd. Currently supported parameters are
     as follows:

     lockd_listen_backlog=num

         Set  connection  queue   length   for   lockd   over   a
         connection-oriented  transport.  The default and minimum
         value is 32. Equivalent to -l option.


     lockd_servers=num

         Maximum number of concurrent lockd requests. The default
         is 20. Equivalent to the nthreads operand.


     lockd_retransmit_timeout=num

         Retransmit timeout, in seconds,  before  lockd  retries.
         The default is 5. Equivalent to -t option.


     grace_period=num

         Grace period, in seconds, that all clients (both NLM and
         NFSv4) have to reclaim locks after a server reboot. This
         parameter also controls the NFSv4  lease  interval.  The
         default is 90. Equivalent to -g option.



     See EXAMPLES, below.

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 grace_period property described above.



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System Administration Commands                          lockd(1M)



     -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  con-
         nect  requests  start  to get dropped. Equivalent of the
         lockd_listen_backlog property described above.


     -t timeout

         Specify the number of seconds to wait before retransmit-
         ting  a  lock  request to the remote server. The default
         value    is    5    seconds.    Equivalent    of     the
         lockd_retransmit_timeout property described above.


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 property described above.


EXAMPLES
     Example 1 Setting a lockd Property


     The following command sets  lockd_listen_backlog  to  a  new
     value:


       # sharectl set -p lockd_listen_backlog=40 nfs




     The lockd_listen_backlog  and  other  lockd  properties  are
     described under NOTES, below.


     Example 2 Getting a lockd Property Value


     The  following  command   retrieves   the   value   of   the
     lockd_listen_backlog property.




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System Administration Commands                          lockd(1M)



       % sharectl get -p lockd_listen_backlog nfs
       lockd_listen_backlog=40



ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Availability                | system/file-system/nfs      |
    |_____________________________|_____________________________|


SEE ALSO
     svcs(1),  automountd(1M),  clear_locks(1M),   mount_nfs(1M),
     share(1M),     share_nfs(1M),    sharectl(1M),    statd(1M),
     svcadm(1M), fcntl(2), lockf(3C), attributes(5), smf(5)

NOTES
     The lockd daemon might not exist  in  a  future  release  of
     Solaris.





























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