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NAME

       ganeti-masterd - ganeti master daemon

SYNOPSIS

       ganeti-masterd  [ -f ] [ -d ] [ --no-voting ]

DESCRIPTION

       The  ganeti-masterd  is the daemon which is responsible for the overall
       cluster coordination. Without it, no change can  be  performed  on  the
       cluster.

       For  testing purposes, you can give the -f option and the program won’t
       detach from the running terminal.

       Debug-level message can be activated by giving the -d option.

   ROLE
       The role of the master daemon is to coordinate  all  the  actions  that
       change  the  state  of  the  cluster.  Things  like accepting new jobs,
       coordinating the changes on nodes (via RPC calls to the respective node
       daemons),  maintaining  the  configuration  and so on are done via this
       daemon.

       The only action that can be done  without  the  master  daemon  is  the
       failover  of  the  master  role to another node in the cluster, via the
       gnt-cluster masterfailover command.

       If the master daemon is stopped, the instances are  not  affected,  but
       they won’t be restarted automatically in case of failure.

   STARTUP
       At  startup,  the master daemon will confirm with the node daemons that
       the node it is running is indeed the master node  of  the  cluster.  It
       will  abort  if  it doesn’t get half plus one positive answers (offline
       nodes are queried too, just in case our configuration is stale).

       For small clusters with a number of nodes down, and especially for two-
       node clusters where the other has gone done, this creates a problem. In
       this case the --no-voting option can be used to skip this process.  The
       option  requires interactive confirmation, as having two masters on the
       same cluster is a very dangerous situation and will most likely lead to
       data loss.

   JOB QUEUE
       The    master   daemon   maintains   a   job   queue   (located   under
       /var/lib/ganeti/queue) in which all current jobs are  stored,  one  job
       per  file  serialized  in JSON format; in this directory a subdirectory
       called archive holds archived job files.

       The moving of jobs from the current to the queue directory is done  via
       a request to the master; this can be accomplished from the command line
       with the gnt-job archive or gnt-job autoarchive commands.  In  case  of
       problems  with  the  master,  a  job  file  can simply be moved away or
       deleted (but this might leave the cluster inconsistent).

   COMMUNICATION PROTOCOL
       The master accepts commands over a Unix socket, using  JSON  serialized
       messages  separated  by a specific byte sequence. For more details, see
       the design documentation supplied with Ganeti.

REPORTING BUGS

       Report bugs to  <URL:http://code.google.com/p/ganeti/> or  contact  the
       developers using the ganeti mailing list <ganeti@googlegroups.com>.

SEE ALSO

       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
       commands).

       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

       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.