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       ganeti-watcher - ganeti cluster watcher




       The  ganeti-watcher  is  a periodically run script which is responsible
       for keeping the instances in the correct status. It  has  two  separate
       functions,  one  for the master node and another one that runs on every

       Its primary function is to try to keep running all instances which  are
       marked  as  up  in  the  configuration  file, by trying to start them a
       limited number of times.

       Its other function is to ‘‘repair’’  DRBD  links  by  reactivating  the
       block  devices  of  instances which have secondaries on nodes that have
       been rebooted.

       The watcher will restart any down daemons that are appropriate for  the
       current node.

       In  addition,  it  will  execute  any  scripts  which  exist  under the
       ‘‘watcher’’    directory    in    the    ganeti     hooks     directory
       (/etc/ganeti/hooks).  This should be used for lightweight actions, like
       starting any extra daemons.

       If the cluster parameter  maintain_node_health  is  enabled,  then  the
       watcher  will  also  shutdown instances and DRBD devices if the node is
       declared as offline by known master candidates.

       The watcher does synchronous queries but will submit jobs for executing
       the  changes.  Due  to  locking, it could be that the jobs execute much
       later than the watcher executes them.


       The command has a state file  located  at  /var/lib/ganeti/
       (only     used    on    the    master)    and    a    log    file    at
       /var/log/ganeti/watcher.log. Removal of either  file  will  not  affect
       correct  operation;  the  removal of the state file will just cause the
       restart counters for the instances to reset to zero.


       Report bugs to  <URL:> or  contact  the
       developers using the ganeti mailing list <>.


       Ganeti  overview  and  specifications:  ganeti(7)  (general  overview),
       ganeti-os-interface(7) (guest OS definitions).

       Ganeti commands:  gnt-cluster(8)  (cluster-wide  commands),  gnt-job(8)
       (job-related   commands),  gnt-node(8)  (node-related  commands),  gnt-
       instance(8) (instance commands), gnt-os(8) (guest  OS  commands),  gnt-
       backup(8)   (instance   import/export  commands),  gnt-debug(8)  (debug

       Ganeti  daemons:  ganeti-watcher(8)  (automatic  instance   restarter),
       ganeti-cleaner(8)  (job  queue cleaner), ganeti-noded(8) (node daemon),
       ganeti-masterd(8) (master daemon), ganeti-rapi(8) (remote API  daemon).


       Copyright  (C) 2006, 2007, 2008, 2009 Google Inc. Permission is granted
       to copy, distribute and/or modify under the terms of  the  GNU  General
       Public  License  as  published  by the Free Software Foundation; either
       version 2 of the License, or (at your option) any later version.

       On Debian systems, the complete text of the GNU General Public  License
       can be found in /usr/share/common-licenses/GPL.