I have the need to use Replistor to migrate my VM's to a DR site. I have followed the EMC and ESX guide 300-006-716 and it's pretty straight forward. Basically I have a VM on my DR ESX server that is used to received replicated data from my production VM's. Following the guide, I add HD's to DR VM, replicate the drives, and then I detach and reattach the HD's to new VM's that I create in the DR site. Where I am having issue is the OS HD's. The guide is referring to replicating the OS drives to drives that already have been made bootable:

In order for the destination location to be bootable, you must replicate data to a disk (Virtual Disk or Mapped Raw LUN) that already has boot sector information in place.

So, if I am to add a second drive to an existing VM to be used as a target for replication of an OS drive, how do I make that drive bootable?

Thanks