On Thu, Oct 20, 2005 at 05:53:05PM +0100, Weber, Philip wrote:
> Master/Media :  Solaris 9 with NBU 5.1.
> Client :  Win2K / Win2003.
> Storage :  EMC Clariion / IBM ESS.
> 
> Hi all, we have got a couple of Windows fileservers of around 1.5 Tb
> (which is a lot of data for us, at least in terms of the time taken to
> back up...)

We've got 20TB on a 4-node Windows cluster here.  This comprises about
300 million files.  Now that sucks :-(.  We're lucky in that the vast
majority of our data isn't changed so we have the opportunity to
write-lock volumes and do less frequent backups on them.

> We have had some success with Solaris & Oracle, using Advanced Client to
> backup offhost (media server) with Vxfs / nbu_snap snapshots and I would
> like to do the same sort of thing for our Windows clients.  However, the
> options seem to be more limited, i.e. to FlashSnap and offhost/alternate
> client.  I am not sure this would get the data off the network and onto
> the fibre or how relevant FlashSnap would be for us.

FlashBackup actually works fairly well - finally after several years of
it not working at all with Solaris masters.  What we've found is that a
24-hour backup can be cut in half by using disk staging units.  Using
FlashBackup cuts the time in half again so we're in the 6-hour range for
a 250GB volume containing 10M files.

> Ideally I would like to
> o  use some snapshot technology to potentially keep backup images for
> restore

See above.

> o  transfer data over the fibre rather than network

This doesn't accomplish that.  You could make this a SAN media server
but you'll be sorry you did.  We've found that the media servers need to
be rebooted fairly frequently after events like tape drive replacements.

> o  remove load from the client

FlashBackup significantly reduces the load on the client compared to a
traditional backup that walks the file system.

> o  split the backup more sensibly i.e. without being limited to the
> drive letters

We're using mount points extensively and FlashBackup supports that now.

> (o  and reduce the amount of data ... but that's another discussion!)

You could do less frequent fulls and combine these with incrementals for
synthetic fulls.  I don't know how well this works, if at all, with
FlashBackup.

-- 
Ed Wilts, Mounds View, MN, USA
mailto:ewilts AT ewilts DOT org