ADD/REMOVE/REPLACE/MOVE Oracle Cluster Registry (OCR) and Voting Disk

Posted By Sagar Patil

Note: You must be logged in as the root user, because root owns the OCR files.  Make sure there is a recent copy of the OCR file before making any changes: ocrconfig ­showbackup

If there is not a recent backup copy of the OCR file, an export can be taken for the current OCR file.

Use the following command to generate an export of the online OCR file:
ocrconfig ­export <OCR export_filename> -s online
If you should need to recover using this file, the fol owing command can be used:
ocrconfig import <OCR export_filename>

1. To add an OCR device:
To add an OCR device, provide the ful path including file name.

ocrconfig -replace ocr <filename>
To add an OCR mirror device, provide the ful path including file name.

ocrconfig -replace ocrmirror <filename>
2. To remove an OCR device:
To remove an OCR device:

ocrconfig -replace ocr
To remove an OCR mirror device

ocrconfig -replace ocrmirror
3. To replace or move the location of an OCR device:
To replace the OCR device with <filename>, provide the ful path including file name.

ocrconfig -replace ocr <filename>
To replace the OCR mirror device with <filename>, provide the ful path including file name.

ocrconfig -replace ocrmirror <filename>

Example moving OCR file from OCFS to raw devices
The OCR disk must be owned by root, must be in the oinstal group, and must have permissions set to 640.
In this example the OCR files are located in the ocfs2 file system:
/ocfs2/ocr1
/ocfs2/ocr2

Create raw device files of at least 100 MB. In this example the new OCR file wil be on the fol owing devices:
/dev/raw/raw1
/dev/raw/raw2
Once the raw devices are created, use the dd command to zero out the device and make sure no data is written
to the raw devices:
dd if=/dev/zero of=/dev/raw/raw1
dd if=/dev/zero of=/dev/raw/raw2

Note: Use UNIX man pages for additional information on the dd command.Now you are ready to move/replace the OCR file to the new storage location.

Move/Replace the OCR device
ocrconfig -replace ocr /dev/raw/raw1
Add /dev/raw/raw2 as OCR mirror device

ocrconfig -replace ocr /dev/raw/raw2
Example of adding an OCR device file
If you have upgraded your environment from a previous version, where you only had one OCR device file, you can
use the fol owing step to add an additional OCR file.
In this example a second OCR device file is added:
Add /dev/raw/raw2 as OCR mirror device

ocrconfig -replace ocr /dev/raw/raw2
ADD/DELETE/MOVE Voting Disk
Note: crsctl votedisk commands must be run as root
Note: Only use the -force flag when CRS is down
Shutdown the Oracle Clusterware (crsctl stop crs as root) on al nodes before making any modification to the
voting disk. Determine the current voting disk location using:
crsctl query css votedisk
Take a backup of al voting disk:

dd if=voting_disk_name of=backup_file_name
Note: Use UNIX man pages for additional information on the dd command.  The following can be used to restore the voting disk from the backup file created.

dd if=backup_file_name of=voting_disk_name
1. To add a Voting Disk, provide the full path including file name.:

crsctl add css votedisk <RAW_LOCATION> -force
2. To delete a Voting Disk, provide the full path including file name.:

crsctl delete css votedisk <RAW_LOCATION> -force
3. To move a Voting Disk, provide the full path including file name.:

crsctl delete css votedisk <OLD_LOCATION> ­force
crsctl add css votedisk <NEW_LOCATION> ­force
After modifying the voting disk, start the Oracle Clusterware stack on al nodes

crsctl start crs
Verify the voting disk location using

crsctl query css votedisk

1> Example : Moving Voting Disk from OCFS to raw devices. The voting disk is a partition that Oracle Clusterware uses to verify cluster node membership and status.
The voting disk must be owned by the oracle user, must be in the dba group, and must have permissions set to 644. Provide at least 20 MB disk space for the voting disk.
In this example the Voting Disks are located in the ocfs2 file system:
/ocfs2/voting1
/ocfs2/voting2
/ocfs2/voting3
Create raw device files of at least 20 MB. In this example the new voting disks wil be on the fol owing devices:
/dev/raw/raw3
/dev/raw/raw4
/dev/raw/raw5

Once the raw devices are created, use the dd command to zero out the device and make sure no data is written to the raw devices:
dd if=/dev/zero of=/dev/raw/raw3
dd if=/dev/zero of=/dev/raw/raw4
dd if=/dev/zero of=/dev/raw/raw5

Now you are ready to move/replace the voting disks to the new storage location.

To move a Voting Disk to new storage location:
crsctl delete css votedisk /ocfs2/voting1 ­force
crsctl add css votedisk /dev/raw/raw3 ­force
crsctl delete css votedisk /ocfs2/voting2 ­force
crsctl add css votedisk /dev/raw/raw4 ­force
crsctl delete css votedisk /ocfs2/voting3 ­force
crsctl add css votedisk /dev/raw/raw5 ­force

2> Example of adding Voting Disks
If you have upgraded your environment from a previous version, where you only had one voting disk, you can use
the fol owing steps to add additional voting disk.
In this example 2 additional Voting Disks are added:

crsctl add css votedisk /dev/raw/raw4 ­force
crsctl add css votedisk /dev/raw/raw5 ­force
After modifying the voting disk, start the Oracle Clusterware stack on al nodes

crsctl start crs
Verify the voting disk location using
crsctl query css votedisk

References
Note 390880.1 – OCR Corruption after Adding/Removing voting disk to a cluster when CRS stack is running

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