XenServer – Apply patches using bash script

#!/bin/bash
#dpthakar@gmail.com
#http://www.linuxreaders.com
 
#with the citrix xenserver 6.2 release, free xencenter can not be used to patch servers. this script can be used on any of server to patch itself & rest of the xenservers, this script is only tested with stanalone servers, no pool etc.
#pl make sure updates stored under PATCHDIR is for SERVERS mentioned here, e.g patches stored for 6.2 only. Also do not mix diff ver of patches & servers.
NFSSHARE=192.168.1.24:/storage/xen_back
MOUNTDIR=/mnt/back
PATCHDIR=/mnt/back/up
#mention list of the xenserver ip
SERVERS="192.168.1.1,192.168.1.2,192.168.1.3,192.168.1.4"
SUSER=root
SPASS=redhat
 
#check for backup / mount dir.
if [ -d $MOUNTDIR ]
        then
                echo "Mount Dir Exists"
        else
                echo "Mount Dir does not exists, Creating"
                mkdir -p $MOUNTDIR
fi
 
#mount nfs share if not already mounted.
MOUNT=`mount|grep $NFSSHARE -c`
if [ $MOUNT = "1" ]
        then
                echo "NFS already mouted"
        else
                echo "Mounting NFS share"
                mount -t nfs $NFSSHARE $MOUNTDIR
fi
 
 
#list patches for patchdir
PLIST=`ls $PATCHDIR/*.xsupdate | wc -l`
PCOUNT=0
PLINE=1	
ls $PATCHDIR/*.xsupdate > /tmp/patch_list
until [ "$PCOUNT" = "$PLIST" ]	
	do
	PATCH=`gawk FNR==$PLINE /tmp/patch_list`
 
	#upload patch file to all mentioned servers
	echo $SERVERS | sed 's/,/\n/g' > /tmp/patch_server_list
	SLIST=`cat /tmp/patch_server_list | wc -l`
	COUNT=0
	LINE=1
	until [ "$COUNT" = "$SLIST" ]
        	do
			SERVER=`gawk FNR==$LINE /tmp/patch_server_list`
			#upload patch to server
			PATCHUUID=`xe -s $SERVER -u $SUSER -pw $SPASS patch-upload file-name=$PATCH`
			#find server uuid
			HOSTUUID=`xe -s $SERVER -u $SUSER -pw $SPASS host-list params=uuid | gawk -F: '{ print $2 }' | sed 's/ //g' | sed '/^$/d'`
			#apply patch
			echo "Patching $PATCH to Server $SERVER"
			xe -s $SERVER -u $SUSER -pw $SPASS patch-apply uuid=$PATCHUUID host-uuid=$HOSTUUID
			#clean applied patch file from local storage to save space
			xe -s $SERVER -u $SUSER -pw $SPASS patch-clean uuid=$PATCHUUID 
			COUNT=`expr $COUNT + 1`
			LINE=`expr $LINE + 1`
	        done
	PCOUNT=`expr $PCOUNT + 1`
	PLINE=`expr $PLINE + 1`
	done