Corrective Action for Diskgroup with Disks Having PVIDs [ID 750016.1]

 

Corrective Action for Diskgroup with Disks Having PVIDs [ID 750016.1]

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修改时间:2012-10-20类型:HOWTO状态:PUBLISHED优先级:2 注释 (0)    
 

In this Document

 Goal
 Fix
 References

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Applies to:
Oracle Server - Enterprise Edition - Version 10.1.0.2 to 11.2.0.2 [Release 10.1 to 11.2]
IBM AIX on POWER Systems (64-bit)
IBM AIX Based Systems (64-bit)

 

Goal
You have created a diskgroup with disks having PVID and the diskgroup is in use. There is no diskgroup metadata corruption reported yet. You now know that ASM Disk should not have PVID as alerted in MetaLink Note 353761.1

This note will give the steps to clear the PVID of these ASM Disks.

Fix
When the PVID is set to a disk in a volume group, the PVID is stored in two locations. In Physical disk header ( within first 4K )and in AIX's system object database, called ODM ( Object Data Manager ).

When the diskgroup is created, the disk header information of PVID is overwritten. However, with reboot the OS, from ODM, AIX might try to restore the PVID information onto the disk header,
there by destroying the ASM metadata.

If the ASM disk header Metadata has not been over written by PVID from ODM ( before a reboot ), then you can follow the following steps to update the ODM not to have PVID for the disks:

1] Do not reboot any node.

1.1] Drop one disk at a time from the diskgroup.

1.2] Clear the PVID of the dropped disk

# chdev -l hdisk5 -a pv=clear

Run this on ALL the nodes in case of RAC.

1.3] Check the disk does not have the PVID from ALL the nodes

# lspv

1.4] Add the disk back to the diskgroup

1.5] Do this for all the disks having PVID in the diskgroup, one by one. Take care that the rebalance is complete from the drop/add disk command before going for the next disk.

OR

2] This needs downtime:

2.1] Take 'dd' backup of the disk headers

# dd if=/dev/hdisk5 of=/tmp/d5.txt bs=1024 count=1024

2.2] Shutdown ASM instance ( on ALL the nodes in RAC setup ).

2.3] Clear the PVID

# chdev -l hdisk5 -a pv=clear

Run this on ALL the nodes in case of RAC.

2.4] Check the disk does not have the PVID from ALL the nodes

# lspv

2.5] Start the ASM Instance(s) and mount the diskgroup on ALL the nodes

WARNING:
Point-2 commands overrides the content of the disk header and so could be destructive if not correctly used. If you have any doubt, raise an SR with Oracle Support before any action.