How to Rename a Copied or Cloned ASM Disk Group
ASM is definitely one of the coolest technologies inside the Oracle Database. On the other hand, the ability of the storage arrays to provide a read/write access to a copy or a “snapshot” of its content is something we can easily leverage as an Oracle DBA. For a couple of weeks, I wanted to copy a database stored in an ASM Disk Group with one of those storage technologies and mount it on the same server; unfortunately, this is not supported even with 11.1.0.6. The good news is that I finally overcame all the obstacles to do it in a specific case. This post relates a couple of the tips I used to get to that result.
What You May Want to Know Before You Start
Several people helped me, even if most of them don’t know. Luca Canali did an awesome presentation about ASM at UKOUG. Alexandro Vargas’s Blog is a must-have in the list of your RSS feed if you work with ASM or RAC. Last but not least, Alex Fatkulin rocks when you have a problem with Oracle. I’m very lucky to work 10 metres away from him and other amazing folks at Pythian.
N.B.: What I describe below is among the worst things you can ever do with ASM. You can use it to play around, but never use it with anything other than test data. If you lose something because of me, you’ll be the only one to blame!
I’ve tested the whole process with Oracle 11.1.0.6 on Ubuntu Gutsy Gibbon, based on a previous post I made on this blog. In order to copy the ASM disks, I’ve used the dd command, but it should not make any difference with a storage array command.
