added to libvirt-check NC hook support for 'service' wrapper and 'lib…

…virt-bin' name, as well as debug statements

tools/nc-hooks/libvirt-check.sh

@@ -9,40 +9,65 @@
 
 event=$1
 euca_home=$2
+debug_log=/dev/null 
 
 # only respond to euca-nc-pre-hyp-check events
 if [ "$event" != "euca-nc-pre-hyp-check" ] ; then
+    echo `date` "ignoring event other than euca-nc-pre-hyp-check" >>$debug_log
     exit 0;
 fi
 
 # expect the first parameter to be Eucalyptus home
 if [ "$euca_home" == "" ] ; then
+    echo `date` "ignoring invocation with no Euca home set" >>$debug_log
     exit 0;
 fi
 
-log_file="${euca_home}/var/log/eucalyptus/nc-hooks.log"
+hook_log="${euca_home}/var/log/eucalyptus/nc-hooks.log"
 rootwrap="${euca_home}/usr/lib/eucalyptus/euca_rootwrap"
 
+# ensure we have the privilege-elevating script
 if [ ! -x "$rootwrap" ] ; then
+    echo `date` "ignoring invocation on system without executable $rootwrap" >>$debug_log
     exit 0;
 fi
 
+# find out what the libvirt daemon service is called on this distro
 if [ -x /etc/init.d/libvirtd ] ; then
-    ctrl_cmd="$rootwrap /etc/init.d/libvirtd"
+    service_name="libvirtd"
+elif [ -x /etc/init.d/libvirt-bin ] ; then
+    service_name="libvirt-bin"
 else
+    echo `date` "ignoring invocation on system where we cannot find libvirt" >>$debug_log
     exit 0;
 fi
 
+# prefer using 'service' to init script when available
+if [ -x /sbin/service ] ; then
+    ctrl_cmd="$rootwrap /sbin/service ${service_name}"
+elif [ -x /usr/sbin/service ] ; then
+    ctrl_cmd="$rootwrap /usr/sbin/service ${service_name}"
+else
+    ctrl_cmd="$rootwrap /etc/init.d/${service_name}"
+fi
+echo `date` "will use '$ctrl_cmd [status|restart]" >>$debug_log
+
+# see if livbirt daemon is running and try to 'restart' if not
 if ! $ctrl_cmd status >/dev/null 2>&1 ; then
     if ! $ctrl_cmd restart >/dev/null 2>&1 ; then
-	echo `date` "ERROR failed to restart libvirt daemon" >>$log_file
+	echo `date` "ERROR failed to restart libvirt daemon" >>$hook_log
+	echo `date` "failed to restart libvirt daemon" >>$debug_log
     else
 	if ! $ctrl_cmd status >/dev/null 2>&1 ; then
-	    echo `date` "ERROR restarted libvirt daemon not available" >>$log_file
+	    echo `date` "ERROR the restarted libvirt daemon not available" >>$hook_log
+	    echo `date` "the restarted libvirt daemon not available" >>$debug_log
 	else
-	    echo `date` "INFO  restarted libvirt daemon" >>$log_file
+	    echo `date` "INFO  restarted libvirt daemon" >>$hook_log
+	    echo `date` "restarted libvirt daemon" >>$debug_log
 	fi
     fi
+else
+    echo `date` "libvirt daemon OK" >>$debug_log
 fi
 
 # always return success, so hypervisor check may proceed