Doug,
Others have expressed similar views but here is what we do with our 5GB DB.
Have 3 synced copies of the database online, split between scsi & ssa
disks. This should protect us in the case of hardware failures.
Do a DB backup each day and send it offsite.
So even if our whole Computer Room blows up we still have a single copy
offsite, or in an extreme case where this can not be read, we would
role back to the previous day (we keep 10 copies of the databse so
could go back 10 days if needed).
Also, all our tape storage pools have Volume retention periods of 3
days, which strictly means we could only go back 3 days with the
database anyway, as anything more and the DB would be out of sync with
tape volumes. Strictly this should be the same as the number of days
of DB backups being kept.
So if our CR blows up we are left with only a single copy of the most
recent DB backup at our offsite tape store. If you want more
protection simply do another DB backup, immediately following the first
& send it to a different location. They will not be exactly the same
but whether you roll back to 7 am or 7:30am does it really make that
much difference.
Cheers,
Simon
----------
| From: ADSM-L AT VM.MARIST DOT EDU; dagnew AT CHARLOTTEPIPE DOT COM
| From: ADSM-L AT VM.MARIST DOT EDU; dagnew AT CHARLOTTEPIPE DOT COM
| To: ADSM-L AT VM.MARIST DOT EDU
| Subject: DB backup -- a single point of failure??
| Date: Saturday, 13 February, 1999 4:49AM
|
| As I have been building a disaster recovery plan with ADSM, I have been
| trying to identify and eliminate all single points of failure. Now I've run
| up against one that won't go away, the database backup.
|
| As I read the manuals, I note that there is no way to create a duplicate
| copy of the database backup tape. So, if I lose (through media failure or
| whatever) the latest database backup or ANY in the series of the latest full
| and subsequent incremental backups, I cannot restore my database to 'last
| backup'.
|
| Granted, if I have two servers and do a server-to-server backup of the
| database and then copy that archive file, I do get a copy of the database
| backup. But dual servers is not in the current configuration YET and I
| can't find any other way to avoid this single point of failure situation.
|
| Am I just not thinking clearly or is this a legitimate problem??
|
| TIA
|
| Doug Agnew
| DBA
| Charlotte Pipe & Foundry
| dagnew AT charlottepipe DOT com
|
|
| {As always, opinions stated herein are mine alone ......}
|
|
