--> the 2 sites are connected with a small (1mbps or so) link.

Then you have no other option than move data by moving tapes.
The approach would be similar to creating active/active cluster with
manual balancing of the load:
- create two TSM server instances on each site. First instance will be
local production and the second will be remote recovery one.
- make ordinary off-site DBSnapshots and restore them each day on the
other site's second instance. Move copypool volumes accordingly.

Let name sites A and B. Let instances be A1 and A2 on first site and B1,
B2 on second site. Restore DB snapshot from A1 to B2 and checkin A1's
copypool volumes. You have successfully recreated A1 onto B2. Systems in
site B use B1 for backups. Would you recover B1 onto A2 is up to your
policy.

Zlatko Krastev
IT Consultant






Stef Coene <stef.coene AT DOCUM DOT ORG>
Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
15.05.2003 14:26
Please respond to "ADSM: Dist Stor Manager"


        To:     ADSM-L AT VM.MARIST DOT EDU
        cc:
        Subject:        Dual site configuration


Hi all,

Let's say I have 2 sites.  The first site is the production site and the
second site is the standby site.  But the standby site has also some local
servers to backup.  Both sites have a TSM server on AIX and an LTO
library.

The question is, can I somehow copy the TSM data from the first site to
the
second site in such way that it can be used in case a disaster strikes on
the
primary site.  Ideally, the 2 TSM servers should be able to access the
same
data from the nodes.

Some solutions I found so far :

- backup-set : create a backup-set each day for the nodes and move them to
the
other site so we can restore the nodes data without the TSM server.  But
this
will require a lot of data movement between the 2 sites.

- remote offsite storage pool copy : the data on the primary site can be
backuped to the second site.  But this requires a restore of the primary
site
if we want to access that data.

- restore primary site on second site : backup the second site and remove
the
tapes out of the library.  After that we can restore the primary site on
the
hardware of the second site.  This also requires that we have a backup of
the
data of the primary site.  This can be done with offsite tapes that are
daily
made.  This also made the TSM server on the second site unavailable for
backup and restore of local NT-servers.

What I really need is 2 TSM servers who replicated the date between them.
So
clients can backup and restore to both servers.

Any input is welcome.

Stef

--

stef.coene AT docum DOT org
 "Using Linux as bandwidth manager"
     http://www.docum.org/
     #lartc @ irc.oftc.net