Q: Should I install a System
Center Data Protection Manager
(DPM) 2007 agent on my guest
OS virtual server?
A: It depends on what you want to
protect. If you install a DPM agent on
the virtual server’s main DPM 2007
administrator console, you can protect
only virtual machines (VMs)—you
can’t protect any applications run by
the VMs. If you deploy the agent in the
guest OS, you can protect everything
the VM runs. For example, if the VM
runs Microsoft SQL Server, you can
protect the databases and capture the
transaction log data.
There are also licensing considerations.
If you deploy the DPM agent in
the guest OSs, they each need an agent
license.
This doesn’t mean that protection
at the virtual-server level is inconsistent.
Virtual Server 2005 R2 SP1 has a
recursive Volume Shadow Copy Service
(VSS) writer, so when DPM 2007 asks
the virtual server for a snapshot, the
request is passed to all VM VSS writers
and you get a consistent data backup.
—John Savill