Evacuating instances on a compute hardware failure

# Pass in the hypervisor to get the list of instances
# Sometimes a whole compute node evacuate may fail
if [[ -z $1 ]]; then
	echo "Pass in a hypervisor, such as compute018.bbh.cyberschool.army.mil"
	exit
fi
nova hypervisor-servers $1 > /tmp/hypervisorinstances
while read line; do
   instanceUUID=`echo $line | cut -d'|' -f2`
   # Only get the Server UUIDs and ignore the header lines, could change to a regex check
   if [[ `echo $instanceUUID | wc -c` -eq 37 ]]; then
       echo "=================================> instance - $instanceUUID"
	   # depending on the state of the instance only evacuate maybe required
	   # Ran it without reset-state first which gets active
	   # nova reset-state --active $instanceUUID
	   nova evacuate $instanceUUID
	   # Reboot can be used if there are issues not starting on the new compute
	   # nova reboot --hard $instanceUUID
	   openstack server show $instanceUUID
	   echo "==========================================================="
   fi
done < /tmp/hypervisorinstances