On this 5th scenario we lose the ASM Spfile.
The ASM spfile in this case is located on a Raw Device, so backup and recovery from and to a Raw Device is explained.
Backup and restore using create pfile from spfile and create spfile from pfile can also be used. In this case it will be necessary to shutdown the database and ASM instances, then start the ASM instance with the pfile and recreate the spfile.
To simulate the ASM spfile loss we
write zeros to it's raw device; because the ASM spfile is accessed only at startup this loss does not affect online work with the database or ASM instances.
- Restore the ASM spfile from backup using dd
- Check
Important! : Before running a crash scenario be sure to Backup the ASM Spfile, details to backup it are included on the attached file.
Comments (3)
Hi Alejandro,
What's the benefits of using spfile for ASM/RAC? In 10gR1 installation, the choice for pfile is the first option there. Can we put spfile into disk group managed by ASM? What's the benefits of storing spfile into RAW disk versus ASM disk group for RAC?
Thanks,
Hai
Posted by hai wu | May 8, 2007 2:10 PM
Posted on May 8, 2007 14:10
Hello,
On RAC with ASM, we create the ASM spfile on a shared location outside ASM disk groups, because in order to mount the ASM disk groups at startup you need to read the spfile before.
The database spfile can be located on ASM, because ASM must be up in order to open a database based on it.
I prefer ocfs2 instead of raw for OCR, voting disk and ASM spfile, but in many sites prefer to use raw devices instead, in OS's other than linux you may be forced to use raw devices if you dont want to use a third party cluster file system.
Posted by Alejandro Vargas | May 8, 2007 9:51 PM
Posted on May 8, 2007 21:51
Excellent job. We are implementing RAC currently and these recovery scenarios really help us in preparing a bullet proof backup strategy
Thanks
Vijay.Cherukuri
Posted by Hi Alejandro, | March 13, 2008 11:14 AM
Posted on March 13, 2008 11:14