DB2 HADR

magnus_nyvall · ‎2012-01-30

I have been asked to investigate how to best take snapshot backup on an DB2 HADR system.

As far as i understand Snapcreator can be used on the Active DB2 server.

I am unsure how to handle the Standby server.

And what to do after a HADR takeover when the standby server becomes the active one.

How to handle snapvault backups etc.

Anyone have any tips or information on this?

Is Snapcreator at all supported on a DB2 HADR system?

Reagrds Magnus

oommen · ‎2012-01-30

Magnus,

1. You can use Snap Creator to do the Backup of HADR primary, and leave the Standby alone. The DB2 system table information gets replicated to the Standby so there is no need to do another Snap at Standby.

2. In the event of a DR, the HADR standby gets active and you run Snap Creator from Standby.

3. If SnapMirror is involved b/w Primary and Standby, all you will do is a re-sync.

4. When you have SnapVault configured, you send Snaps to SV, and during a recovery you re-initialize the HADR standby.

From the support perspective, HADR is a feature of DB2 and since DB2 is supported, yes HADR is also supported. If you have any questions please do let me know.

Bobby.

magnus_nyvall · ‎2012-01-30

1 and 2 makes perfect sense to me.

But i do not quite understand 3 and 4.

Could you elaborate a bit?

Regards Magnus

oommen · ‎2012-01-30

Sorry for not being specific,

#3 HADR is not intended for remote site replication with longer distance. If you have a SM relationship to a distant DR location you can use Snap Creator to do a SM transfer to the distant DR site. During a Site failover,

1. Activate DR location by breaking SM relationship.

2. Re-sync SM once Primary is up to change the SM direction

3. Switch Back to Primary

3. Re-initialize the HADR standby using Backup from Primary

#4 When you have SV setup and would like to use a Snap from SV to recover the database, you would

1. Stop HADR and bring DB2 down.

2. Do a SV restore and activate the Primary

3. Re-do the HADR setup to activate the Standby.

Please feel free to contact me, if you have any questions.

Bobby Oommen