On Oct 19, 2004, at 6:58 AM, Rowan O'Donoghue wrote:

In an environment where you are using HSM to manage disks (say for
example
Windows drives).... after a period of time the file will be migrated
to a
storage pool within TSM and a stub file is left on the filesystem as a
marker.

I'm assuming that when this migration happens the TSM backup/archive
client
identifies the change and only backs up the stub - or does it need to
recall the file from HSM and then back it up? If it does only backup
the
stub the issue is that you do not have a copy of a real file only a
stub
and no data.

Can someone give me an idea as to how they have this type of scenario
implemented within their environment?

Rowan - TSM never backs up HSM stub files, as that would be pointless.
               It backs up the file, either from the file system or directly
from the HSM storage pool if migrated and using same server.

See the (old) HSM redbook at
 http://www.redbooks.ibm.com/abstracts/sg244631.html
which explains how it all works in different configurations, and advises
on restoral methods.

  Richard Sims    http://people.bu.edu/rbs