NAME

       sge_shadowd - Sun Grid Engine shadow master daemon

SYNOPSIS

       sge_shadowd

DESCRIPTION

       sge_shadowd  is  a "light weight" process which can be run on so-called shadow master hosts in a Sun Grid
       Engine cluster to detect failure of the current Sun Grid Engine master  daemon,  sge_qmaster(8),  and  to
       start-up  a  new sge_qmaster(8) on the host on which the sge_shadowd runs. If multiple shadow daemons are
       active in a cluster, they run a protocol which ensures that only one of them will start-up a  new  master
       daemon.

       The   hosts suitable for being used as shadow master hosts must have shared root read/write access to the
       directory $SGE_ROOT/$SGE_CELL/common as well  as  to  the  master  daemon  spool  directory  (by  default
       $SGE_ROOT/$SGE_CELL/spool/qmaster).   The  names  of  the shadow master hosts need to be contained in the
       file $SGE_ROOT/$xQS_NAME_Sxx_CELL/common/shadow_masters.

RESTRICTIONS

       sge_shadowd may only be started by root.

ENVIRONMENT VARIABLES

       SGE_ROOT       Specifies the location of the Sun Grid Engine standard configuration files.

       SGE_CELL       If set, specifies the default Sun Grid Engine cell. To address  a  Sun  Grid  Engine  cell
                      sge_shadowd uses (in the order of precedence):

                             The name of the cell specified in the environment variable SGE_CELL, if it is set.

                             The name of the default cell, i.e. default.

       SGE_DEBUG_LEVEL
                      If  set,  specifies  that  debug  information should be written to stderr. In addition the
                      level of detail in which debug information is generated is defined.

       SGE_QMASTER_PORT
                      If set, specifies the  tcp  port  on  which  sge_qmaster(8)  is  expected  to  listen  for
                      communication  requests.  Most installations will use a services map entry for the service
                      "sge_qmaster" instead to define that port.

       SGE_DELAY_TIME This variable controls the interval in which sge_shadowd pauses if a takeover  bid  fails.
                      This  value  is  used  only  when  there  are  multiple sge_shadowd instances and they are
                      contending to be the master.  The default is 600 seconds.

       SGE_CHECK_INTERVAL
                      This variable controls the interval in which the sge_shadowd checks the heartbeat file (60
                      seconds by default).

       SGE_GET_ACTIVE_INTERVAL
                      This variable controls the interval when a sge_shadowd instance tries to  take  over  when
                      the heartbeat file has not changed.

FILES

       <sge_root>/<cell>/common
                       Default configuration directory
       <sge_root>/<cell>/common/shadow_masters
                       Shadow master hostname file.
       <sge_root>/<cell>/spool/qmaster
                       Default master daemon spool directory
       <sge_root>/<cell>/spool/qmaster/heartbeat
                       The heartbeat file.

SEE ALSO

       sge_intro(1), sge_conf(5), sge_qmaster(8), Sun Grid Engine Installation and Administration Guide.

COPYRIGHT

       See sge_intro(1) for a full statement of rights and permissions.

SGE 6.2u5                                            $Date$                                       SGE_SHADOWD(8)