Update Method Code Listing

The RGM calls the Update method to notify a running resource that its properties have been changed.

Example A-10 dns_update Method

#!/bin/ksh
# Update method for HA-DNS.
# The actual updates to properties are done by the RGM. Updates affect only 
# the fault monitor so this method must restart the fault monitor.

#pragma ident   “@(#)dns_update   1.1   12/01/24”

###############################################################################
# Parse program arguments.
#
function parse_args # [args ...]
{
        typeset opt

        while getopts `R:G:T:' opt
        do
                case “$opt” in
                R)
                        # Name of the DNS resource.
                        RESOURCE_NAME=$OPTARG
                        ;;
                G)
                        # Name of the resource group in which the resource is
                        # configured.
                        RESOURCEGROUP_NAME=$OPTARG
                        ;;
                T)
                        # Name of the resource type.
                        RESOURCETYPE_NAME=$OPTARG
                        ;; 
                *)
                    logger -p ${SYSLOG_FACILITY}.err \
                    -t [$RESOURCETYPE_NAME,$RESOURCEGROUP_NAME,$RESOURCE_NAME] \
                    “ERROR: Option $OPTARG unknown”
                     exit 1
                     ;;
                esac
        done
}
###############################################################################
# MAIN
###############################################################################
export PATH=/bin:/usr/bin:/usr/cluster/bin:/usr/sbin:/usr/proc/bin:$PATH

# Obtain the syslog facility to use to log messages.
SYSLOG_FACILITY=`scha_cluster_get -O SYSLOG_FACILITY`

# Parse the arguments that have been passed to this method
parse_args “$@”

PMF_TAG=$RESOURCE_NAME.monitor
SYSLOG_TAG=$RESOURCETYPE_NAME,$RESOURCEGROUP_NAME,$RESOURCE_NAME

# Find where the probe method resides by obtaining the value of the 
# RT_basedir property of the resource.
RT_BASEDIR=`scha_resource_get -O RT_basedir -R $RESOURCE_NAME \
-G $RESOURCEGROUP_NAMÈ

# When the Update method is called, the RGM updates the value of the property
# being updated. This method must check if the fault monitor (probe)
# is running, and if so, kill it and then restart it.
if pmfadm -q $PMF_TAG.monitor; then

# Kill the monitor that is running already
        pmfadm -s $PMF_TAG.monitor TERM
        if [ $? -ne 0 ]; then
                logger -p ${SYSLOG_FACILITY}.err -t [$SYSLOG_TAG] \
                    “${ARGV0} Could not stop the monitor”
                exit 1
        else
                # Could successfully stop DNS. Log a message.
                logger -p ${SYSLOG_FACILITY}.info -t [$SYSLOG_TAG] \
                    “Monitor for HA-DNS successfully stopped”
        fi
   # Restart the monitor.
   pmfadm -c $PMF_TAG.monitor -n -1 -t -1 $RT_BASEDIR/dns_probe \
      -R $RESOURCE_NAME -G $RESOURCEGROUP_NAME -T $RESOURCETYPE_NAME
   if [ $? -ne 0 ]; then
          logger -p ${SYSLOG_FACILITY}.err -t [$SYSLOG_TAG] \
                  “${ARGV0} Could not restart monitor for HA-DNS “
      exit 1
   else
      logger -p ${SYSLOG_FACILITY}.info -t [$SYSLOG_TAG] \
                    “Monitor for HA-DNS successfully restarted”
   fi
fi
exit 0