Name

       ganeti-watcher - Ganeti cluster watcher

Synopsis

       ganeti-watcher [--debug] [--job-age=*age* ] [--ignore-pause] [--rapi-ip=*IP*] [--no-verify-disks]

DESCRIPTION

       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 node.

       If  the  watcher  is  disabled at cluster level (via the gnt-cluster watcher pause command), it will exit
       without doing anything.  The cluster-level pause can be overridden via the --ignore-pause option, for ex‐
       ample if during a maintenance the watcher needs to be disabled in general, but the administrator wants to
       run it just once.

       The --debug option will increase the verbosity of the watcher and also activate logging to  the  standard
       error.

       The  --rapi-ip  option  needs to be set if the RAPI daemon was started with a particular IP (using the -b
       option).  The two options need to be exactly the same to ensure that the watcher can reach the  RAPI  in‐
       terface.

   Master operations
       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.

       Another function is to "repair" DRBD links by reactivating the block devices of instances which have sec‐
       ondaries on nodes that have been rebooted.

       Additionally, it will verify and repair degraded DRBD disks; this will not happen,  if  the  --no-verify-
       disks option is given.

       The watcher will also archive old jobs (older than the age given via the --job-age option, which defaults
       to 6 hours), in order to keep the job queue manageable.

   Node operations
       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 (@SYSCONFDIR@/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 submits them.

FILES

       The command has a set of state files (one per group) located at @LOCALSTATEDIR@/lib/ganeti/watcher.GROUP-
       UUID.data (only used on the master) and a log file at @LOCALSTATEDIR@/log/ganeti/watcher.log.  Removal of
       either  file(s)  will  not  affect  correct  operation; the removal of the state file will just cause the
       restart counters for the instances to reset to zero, and mark nodes as freshly rebooted (so  for  example
       DRBD minors will be re-activated).

       In  some cases, it's even desirable to reset the watcher state, for example after maintenance actions, or
       when you want to simulate the reboot of all nodes, so in this case, you can remove all state files:

              rm -f @LOCALSTATEDIR@/lib/ganeti/watcher.*.data
              rm -f @LOCALSTATEDIR@/lib/ganeti/watcher.*.instance-status
              rm -f @LOCALSTATEDIR@/lib/ganeti/instance-status

       And then re-run the watcher.

REPORTING BUGS

       Report bugs to the project's issue tracker (https://github.com/ganeti/ganeti/issues) or contact  the  de‐
       velopers using the Ganeti mailing list.

SEE ALSO

       Ganeti overview and specifications: ganeti(7) (general overview), ganeti-os-interface(7) (guest OS defin‐
       itions), ganeti-extstorage-interface(7) (external storage providers).

       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-stor‐
       age(8) (storage commands), gnt-group(8) (node group commands), gnt-backup(8) (instance import/export com‐
       mands), gnt-debug(8) (debug commands).

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

       Ganeti htools: htools(1) (generic binary), hbal(1) (cluster balancer), hspace(1) (capacity  calculation),
       hail(1) (IAllocator plugin), hscan(1) (data gatherer from remote clusters), hinfo(1) (cluster information
       printer), mon-collector(7) (data collectors interface).

COPYRIGHT

       Copyright (C) 2006-2015 Google Inc.  All rights reserved.

       Redistribution  and  use in source and binary forms, with or without modification, are permitted provided
       that the following conditions are met:

       1.  Redistributions of source code must retain the above copyright notice, this list  of  conditions  and
       the following disclaimer.

       2.  Redistributions in binary form must reproduce the above copyright notice, this list of conditions and
       the following disclaimer in the documentation and/or other materials provided with the distribution.

       THIS  SOFTWARE  IS  PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
       WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND  FITNESS  FOR  A
       PARTICULAR  PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
       ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMIT‐
       ED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS  INTERRUP‐
       TION)  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (IN‐
       CLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF  ADVISED  OF
       THE POSSIBILITY OF SUCH DAMAGE.

Ganeti                                                                                         ganeti-watcher(8)