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 master-failover 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.

   SHUTDOWN
       When  the  master  daemon receives a SIGINT (Ctrl-C) or SIGTERM signal, it stops accepting
       new jobs and prepares to shut  down  shortly  after  jobs  running  at  the  time  finish.
       Meanwhile it still responds to LUXI requests.  Pending jobs are re-queued after the daemon
       is started again.  When a second signal is received, the master daemon terminates  without
       waiting  (it  might still need to wait for some threads to finish).  Note that the latter,
       as well as sending SIGKILL, may leave the cluster in an inconsistent state.

   JOB QUEUE
       The   master   daemon   maintains   a   job   queue   (located   under    the    directory
       /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  project  website  (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-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-storage(8) (storage commands), gnt-group(8) (node group
       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).

       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, 2007, 2008, 2009, 2010, 2011, 2012 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.