Disaster recovery old bootable cd
I have backup exec 2012 and looking to start using the disaster recovery. I have 2 questions though. Do i need to create a new ISO image every time i have a full backup or do i just create one initially then if i need it months or years down the line do i just boot to that cd and use the latest backup files (i backup to external hard drives). Also can this be backup up on a server and then recovered on new hardware / a totally new server?