DB2 change the database recovery mode

[Former Member]

Hi Friends,

We are doing an upgrade, in the process will be necessary to change the DB recovery mode.

Database is DB2 9.5 and the platform is Unix (AIX). I wold like to clarify the process of change the recovery mode, I underestand that it is to switch off the logg retain, but I have found in some forums that in order to switch on the logg retain, when the upgrade finished, I have to have an full backup of this database.

I need to plan this activity and its effects.

Please do you know something about it, can you clarify me the process?

Thanks a lot.

Regards

Enrique Sánchez

[Former Member · Accepted solution]

The process is pretty straightforward:

1. Shutdown SAP and deactivate the database.

2. Enable recovery mode by setting logarchmeth1 (as user db2<sid>)

db2 update db cfg for <SID> using logarchmeth1 disk:<archivepath> immediate

3. Perform an offline backup of the database (as user db2<sid>)

db2 backup database <sid> to <backuplocation> compress without prompting

The backup time depends on the size of your system. Once the backup is complete, you can activate the database and bring up SAP.

- Sameer

[Former Member · Accepted solution]

Hi Sameer,

Just one question about the point :

" 3. Perform an offline backup of the database (as user db2<sid>)

db2 backup database <sid> to <backuplocation> compress without prompting "

did You mean that this backup is necessary for DB2?

Excuse me but I am new in DB2.

Regards

Enrique.

[Former Member · Accepted solution]

Yes, this backup is necessary if you are switching from a circular logging method to an archival logging method. Once the switch is done, the database will go into a backup pending state and will force you to perform a backup.

- Sameer

[Former Member · Accepted solution]

Thak you very much Sameer.

Enrique Sánchez.

[Former Member]

Hi,

Could you please explain why you think you need to change the recovery mode for the upgrade? At least this is not a requirement from SAP.

Regards,

Joachim

[Former Member]

Hi Joachim,

in the upgrade process , the SAP Upgrade Guide mention "Change the DB recovery mode, if necessary", regulary this condition is followed because of the growing up of DB logs size, therefore you turn off these.

This situation could impact in time because when you switch on the db logs you will need to make a full offline backup as i underestood in the above commentary.