Actually, I had taken the backup of TOMCAT around a week back in preparation of the swap for migration. But, one change is going to happen in our application in the form of a hotfix tomorrow and our migration is scheduled for day after. So, should a backup of TOMCAT be taken after our application hotfix is applied. Also, should a back of java($JAVA_HOME) and ant($ANT_HOME) be taken, we use j2sdk1.4.x for java and apache-ant-1.6.1 for ant.
If you want to take a safe back up I strongly suggest that the server is cleanly shutdown before doing so. Then backing up the entire Jboss server is a good idea. Be aware of file permissions with your backup/restore, you don't want to restore the server with different file permissions than what was there originally (make sure you investigate the tar/zip/unzip options carefully).
If you haven't edited the Java or Ant installs (java you should almost never, Ant you may have added in a few libs) then there's no need to back those up.
thanks, for your answer. Actually, I had taken a copy of JBOSS, TOMCAT, JAVA, ANT on a running server and put it in the new server. It is working fine.
Will try to keep it in mind if next time we require a back-up. Any specific reason why it should be taken from a server which is shutdown because that requires application down-time and has to be justified.
Because of state, during your backup you might for example be picking up a transaction going through the transaction data store, it may have unforseen consequences when you then restore that server and start it up again (it may try to complete that txn again...).