SGE_SHADOWD(8)					      Sun Grid Engine Administrative Commands					    SGE_SHADOWD(8)

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 dae-
       mon.

       The  hosts suitable for being used as shadow master hosts must have shared root read/write access to the directory $SGE_ROOT/$SGE_CELL/com-
       mon  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 infor-
		      mation 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)