Which backup type to use?

[Former Member]

Good day

I need to schedule daily online backups of my SAP Oracle 10 system. The default backup_type for online backups is "online" in DB13.

However, it appears this type of backup is useless in a disaster situation, where I have lost an entire system. I have not been able to get brtools to recognise this backup as a valid backup to restore a system from.

Apparently, the backup_type should be "online_cons" to get a consistent backup from which I can restore. The question then is, what is the function of backup_type online - i.e. under what circumstances can I use this? and, should I rather change table SDBAC so that all my backup_type for online backups is online_cons?

I need to not only ensure that my data is backed up, but also that I can restore it properly.

Thanks

Wilhelm

[Former Member]

Hallo.

I have the same question: if I schedule it on DB13 I am not able to choose online_cons.

I can choose "Whole database onlineredo log backup" from DB13, but if I try to execute a restore, for example "Whole database reset", brtools doesn't propose the backup "Whole database onlineredo log backup", it sees only offline backup or online_cons backup executed from command line, not from DB13.

So, is there a suggestion from SAP to modify SDBAC to include online_cons on DB13 ?

I see Note "859450 - Maintenance of the DB13-command table SDBAC" but it doesn't mention online_cons.

Could you help me?

Thanks.

Mario

[Former Member]

Any news about this problem?

Thanks.

Mario

[Former Member]

Hello

Can you point me to a guide how to use brtools to perform a recovery onto a new server if I use method online + redo log backups. (PS. I am performing hourly archive log backups as well).

I an DR situation I would have lost my primary server, so I have no control files etc.etc. I need to get that back using brtools. The only way I could find that brtools can restore the control file is performing a database reset - and that I can only do if I have a backup of type online_cons.

Do I run in any risk if all my backups are of type online_cons? Can I still do point in time recovery? If so what is the point of the "online" backup type?

Regards

Wilhelm

[Former Member]

Hi Wilhelm,

>> Can you point me to a guide how to use brtools to perform a recovery onto a new server if I use method online + redo log backups. (PS. I am performing hourly archive log backups as well).

Check the link, below;

http://help.sap.com/saphelp_nw70/helpdata/en/93/4ffb72309fb04e80ebfefae1b7a96f/content.htm

>> I an DR situation I would have lost my primary server, so I have no control files etc.etc. I need to get that back using brtools. The only way I could find that brtools can restore the control file is performing a database reset - and that I can only do if I have a backup of type online_cons.

You can check the link, below;

http://help.sap.com/saphelp_media471/helpdata/en/0d/d2ff264a0c11d182b80000e829fbfe/content.htm

Non-database files 
Database data files 
Control files 
Online redo log files 
Offline redo log files 
Oracle profiles init<DBSID>.ora and init<DBSID>.dba 
BRBACKUP/BRARCHIVE profile init<DBSID>.sap 
Main SAPDBA log reorg<DBSID>.log and the structure log struct<DBSID>.log (if it exists, also the script create_raw_links) 
Summary BRBACKUP/BRARCHIVE log 
Detailed BRBACKUP/BRARCHIVE log

Creating control file is the easiest part of it.

>> Do I run in any risk if all my backups are of type online_cons? Can I still do point in time recovery? If so what is the point of the "online" backup type?

with the "online_cons" you just save the offline redolog files created during the online backup for the consistent backup. You need to start "Redolog backup" for the newly created offline redofiles, after the backup.

Best regards,

Orkun Gedik

[Former Member]

Good day

I posted this question to SAP, but they returned that it is a consulting issue. Anyone else has an idea of which backup tupe I should use to be able to perform a restore onto a DR server asd well as able to have daily backups that I can use to perform a point in time recovery to.

Thanks

Wilhelm

[Former Member]

Hi Wilhelm,

As you found out previously, "online_cons" backup is suitable with your needs. In summary, by "online_cons" you will be able to save datafiles, as well as your offline redolog files created during the online backup. But, as you've mentioned previously, you need to create a new record on "SDBAC" table. Plus, you should execute Redo log backup, periodically.

On the other hand, "Whole database online + redo log backup" is looking feasible, at your case. By choosing this strategy, you will be able to save your datafiles and existing offline redolog files. But, for the point in time recovery, you should execute, "Redo log backup", periodically (for example 3 times in a day, but this is depended how many offline redolog files have been created. You will calculate this period value) between your online backup sessions.

My second suggestion matching with your both (DR & having daily backups) needs.

Best regards,

Orkun Gedik

[Former Member]

Hi,

It depends how you plan for recovery.

We use Online abckup daily plus archive every half an hour to two different locations. If we have online backup and redo logs, we can restore it to the point we have redo log files. Only thing we need t omake sure online backup and redo logs are consistent, hnece need to keep atleast two different places.

For DR, we generally do a filesystem backup, and before that make one standby control file. After that restoration to new server and make it running in standby mode is not difficlut, need to know oracle commands which a DB expert can do.

Regards,

Sabita

[Former Member]

Hi

Yes, I tried it on two systems now to make sure. When scheduling the backup from DB13 it uses the parameters defined in SDBAC and ignores the ones in initSID.sap.

Regards

Wilhelm

[Former Member]

Hi,

Ok, I couldn't try it on my system, right away. But if you are planning to change SDBAC, I recommend you that open a ticket to SAP and get a recommendation about it.

Best regards,

Orkun Gedik

[Former Member]

Hi
> 
> Yes, I tried it on two systems now to make sure.  When scheduling the backup from DB13 it uses the parameters defined in SDBAC and ignores the ones in initSID.sap.
> 
> Regards
> Wilhelm

Hi,

Yes, it is correct. I missed that DB13 is executing the command "-t online" parameter. So, it overrides the init<DBSID>.sap file.

Finally, as I recommended you that open a ticket about this issue, in order to prevent unexpected problems.

Best regards,

Orkun Gedik

[Former Member]

Hello

If I change the parameter in fileinit<SID>.sap it has no relevance when executing it from transaction DB13. It only reads this file when executing the command manually. I need to schedule my backups from DB13.

The issue though is, should all my backups be run as online_cons in order to restore them? What is the purpose then of backup type online, even if I have all the redo logs as well? BRTOOLS does not accept it?

Regards

Wilhelm

[Former Member]

Hi Wilhelm,

>> If I change the parameter in fileinit<SID>.sap it has no relevance when executing it from transaction DB13. It only reads this file when executing the command manually.

Are you sure? Schedule a "Whole database online + redolog backup" in DB13 and check "Options for Database Backup (BRBACKUP)" label in the "Action Parameters" Tab.

Best regards,

Orkun Gedik

[Former Member]

>> Apparently, the backup_type should be "online_cons" to get a consistent backup from which I can restore. The question then is, what is the function of backup_type online - i.e. under what circumstances can I use this? and, should I rather change table SDBAC so that all my backup_type for online backups is online_cons?

Hi Wilhelm,

With the "online_cons" parameter, offline redolog files generated during the backup and copied into the same volume with the datafiles. So, you will have a consistent copy of your database.

Check the link, below;

http://help.sap.com/saphelp_45b/helpdata/en/0d/d305f54a0c11d182b80000e829fbfe/content.htm

In order to take online consistent backup, add the parameter into the init<DBSID>.sap, below;

backup_type = online_cons

You don't need to change SDBAC table content.

Best regards,

Orkun Gedik