This is the part of the resource agent that actually executes when the resource agent is invoked. It typically follows a fairly standard structure:

# Make sure meta-data and usage always succeed
case $__OCF_ACTION in
meta-data)      foobar_meta_data
                exit $OCF_SUCCESS
                ;;
usage|help)     foobar_usage
                exit $OCF_SUCCESS
                ;;
esac

# Anything other than meta-data and usage must pass validation
foobar_validate_all || exit $?

# Translate each action into the appropriate function call
case $__OCF_ACTION in
start)          foobar_start;;
stop)           foobar_stop;;
status|monitor) foobar_monitor;;
promote)        foobar_promote;;
demote)         foobar_demote;;
reload)         ocf_log info "Reloading..."
                foobar_start
                ;;
validate-all)   ;;
*)              foobar_usage
                exit $OCF_ERR_UNIMPLEMENTED
                ;;
esac
rc=$?

# The resource agent may optionally log a debug message
ocf_log debug "${OCF_RESOURCE_INSTANCE} $__OCF_ACTION returned $rc"
exit $rc