Hi,

I've a general question concerning back-up strategy and 'how-to-use' ADSM.
Several years age we started using ADSM to back-up our LAN servers because
we were seeing an unstoppable proliferation of LAN back-up hardware attached
to those servers, and an unacceptable growth of the manual operations that
come with that.
Since then, of course, our LAN environment has grown tremendously, and right
now we find ourselves in the following situation:
ADSM 3.1 on OS/390 as server environment
+/- 500 GB of LAN data, on some thirty Windows NT application servers and
5 Novell Netware file servers
daily bacup schedules that back-up about 20 GB of changed data (in total)
mainframe - LAN connection: a 100 Mbit OSA card for the NT clients, 16
Mbit TR OSA card for the Novell clients

In this situation, backing up the changed data is not really a problem: the
longest back-up schedules run 2 to 3 hours. The problem is: data restore.
The fastest performance we're seeing for data restore is +/- 2 GB per hour,
this is for collocated clients. (Non-collocated it's dramatic ...)  If we
want to restore clients with 30 GB or more data on it, we'll need at least
15 to 20 hours to bring the client back up. As you can imagine, that kind of
downtime is unacceptable. The problem is that I've run out of ideas of how
to substantially increase the restore performance, the most importance
bottle necks apparently being the network and the CPU utilisation on
mainframe. So now we've come to a point where we are seriously considering
again attaching DLT drives to our larger servers and backing them up that
way ... back to where we came from, as it were ...

So, a very long explanation just to ask this simple question: are we
overlooking something ? What are you guys out there doing to back-up all
those gigabytes of data and how do you manage to restore them without
sending all your users home for 2 days ?
All ideas are welcome.


Chris De Bondt,
DVV System Engineer

Tel: 02/286.68.29
fax: 02/286.71.60
chris.de.bondt AT dvvlap DOT be