Hi,

We are currently using SAP MaxDB and take snapshot backup.

Soon we would be migrating to Oracle 10g.

Can we take snapshot backup in oracle 10g also ?

If yes, how and would is it as reliable as RMAN Backup ?


Thanks,
Rushabh
Oracle DBA

Hi Rushabh,

"Can we take snapshot backup in oracle 10g also ?"

To Oracle, the word "snapshot" has a different meaning.

If you mean "point in time" backup, yes, Oracle will do that, either cold (database down) or a "hot" backup (database is running).

Here is a good overview of RMAN:

http://www.dba-oracle.com/concepts/rman.htm

I would recommend taking the Oracle course on RMAN before you get started, as it has many options:

http://education.oracle.com/Please/web_pro...001&lang=US

Hi,

Thanks for the information.

I am familiar with RMAN Backup.

Was just confirming if we can go for SNAPSHOT backup in Oracle or not.

I came to know about this through

http://blogs.warwick.ac.uk/java/entry/rman_vs_os

and got a little confused.


Regards,
Rushabh

Can we take snapshot backup in oracle 10g also?

Yes you can. We have set it up ourselves and basically you have to work with your SAN management group to set it up properly. I have not worked on it for a time but you need to make sure that snapshots of files are take in a particular order and particular steps are performed.
Something like:
archive all current log files
Put database in backup mode
snapshot all datafiles
put database out of backup mode
archive all current log files
backup all archive log files
create backup of controlfile (binary and text)
backup controlfile

You may have to play with the order somewhat...but you need a binary copy of the backup controlfile after the backup is complete so that it knows everything up until that point.

Check out the documentation:
http://download.oracle.com/docs/cd/B19306_....102/b14191.pdf

For User-Managed Backups (and depending on your system User-Managed Backups in SUSPEND Mode.
----------
Is it as reliable as an RMAN backup?
Well I would say so in most circumstances.
For our SAP instances the HOT backup works just fine
The COLD backup is not working properly, however I don't think this is a "normal" issue, but one we created ourselves with our system setup.

Regards
Tim

Hi Tim,

Thank you so much.

This is exactly what I wanted.


Regards,
Rushabh
Oracle DBA