How To : OCR / Vote disk Maintenance Operations: (ADD/REMOVE/REPLACE/MOVE)

OCR / Vote disk Maintenance Operations: (ADD/REMOVE/REPLACE/MOVE) [ID 428681.1]
	Modified 23-SEP-2011     Type HOWTO     Status PUBLISHED

In this Document
  Goal
  Solution
  References

---

Applies to:

Oracle Server - Enterprise Edition - Version: 10.2.0.1 to 11.1.0.7 - Release: 10.2 to 11.1
Information in this document applies to any platform.
Oracle Server Enterprise Edition - Version: 10.2.0.1 to 10.2.0.4

Goal

The goal of this note is to provide steps to add, remove, replace or move an Oracle Cluster Repository (OCR) or voting disk in Oracle Clusterware 10g Realese 2 (10.2.0.1 and later) environments. It will also provide steps to move OCR / voting and ASM devices from raw device to block device.

This article is intended for DBA’s and Support Engineers who need to modify, or move OCR and voting disks files, customers who have an existing clustered environment deployed on a storage array and might want to migrate to a new storage array with minimal downtime. 

Typically, one would simply cp or dd the files once the new storage has been presented to the hosts. In this case, it is a little more difficult because:

1. The Oracle Clusterware has the OCR and voting disks open and is actively using them. (Both primary and mirrors)
2. There is a “cluster API” provided for this function (ocrconfig, and crsctl), which is the appropriate interface than typical cp and/or dd commands.

It is highly recommended to take a backup of the voting disk, and OCR device before making any changes. 

Oracle Cluster Registry (OCR) and Voting Disk Additional clarifications

The following steps assume the cluster is setup using Oracle redundancy with 3 voting disks and 2 OCR. 

Solution

ADD/REMOVE/REPLACE/MOVE OCR Device

Note: You must be logged in as the root user, because root owns the OCR files. "crsctl -replace" command can only be issued when CRS is running, otherwise PROT-1: Failed to initialize ocrconfig
will occur.

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:

In 10.2 

# ocrconfig –export -s online

In 11.1

# ocrconfig -manualbackup

node1 2008/08/06 06:11:58 /crs/cdata/crs/backup_20080807_003158.ocr

If you should need to recover using this file, the following command can be used:

# ocrconfig -import

To see whether OCR is healthy, run an ocrcheck, which should return with “succeeded“, like below.

# ocrcheck
Status of Oracle Cluster Registry is as follows :
Version : 2
Total space (kbytes) : 497928
Used space (kbytes) : 312
Available space (kbytes) : 497616
ID : 576761409
Device/File Name : /dev/raw/raw1
Device/File integrity check succeeded
Device/File Name : /dev/raw/raw2
Device/File integrity check succeeded

Cluster registry integrity check succeeded

1. To add an OCRMIRROR device when only OCR device defined:

To add an OCR mirror device, provide the full path including file name. 

# ocrconfig -replace ocrmirror

2. To remove an OCR device:

To remove an OCR device: 

# ocrconfig -replace ocr

* Once an OCR device is removed, ocrmirror device automatically changes to be OCR device.
* It is not allowed to remove OCR device if only 1 OCR device is defined, the command will return PROT-16. 

To remove an OCR mirror device: 

# ocrconfig -replace ocrmirror

After removal, the old OCR/OCRMIRROR can be deleted if they are on cluster filesystem.

3. To replace or move the location of an OCR device:

Note. 1. An ocrmirror must be in place before trying to replace the OCR device. The ocrconfig –replace will fail with PROT-16, if there is no ocrmirror. 
2. If an OCR device is replaced with a device of a different size, the size of the new device will not be reflected until the clusterware is restarted.
3. If OCR is on cluster file system, the new OCR or OCRMIRROR file must be touched first before replace command can be issued. Otherwise PROT-21: Invalid parameter will occur.

To replace the OCR device with , provide the full path including file name.

# ocrconfig -replace ocr

To replace the OCR mirror device with , provide the full path including file name.

# ocrconfig -replace ocrmirror

Example Moving OCR from Raw Device to Block Device

The OCR disk must be owned by  root, in the  oinstall group, and must have permissions set to 640. Provide at least 100 MB disk space for the OCR.

In this example the OCR files will be on the following devices:

/dev/raw/raw1
/dev/raw/raw2

For moving the OCR  from raw device to block device there are two different ways. One, which requires a full cluster outage, and one with no outage. The offline method is recommended for 10.2 and earlier since a cluster outage is required anyways due to an Oracle bug, which prevents online addition and deletion of voting files. This bug is fixed in 11.1, so either online or offline method can be employed in 11.1 onwards.

Method 1 (Online)

If there are additional block devices of same or larger size available, one can perform. 'ocrconfig -replace'.

PROS: No cluster outage required. Run 2 commands and changes are reflected across the entire cluster.

CONS: Need temporary additional block devices with 256MB in size. One can reclaim the storage pointed by the raw devices when the operation completes.

· On one node as root run:

# ocrconfig -replace ocr /dev/sdb1 
# ocrconfig -replace ocrmirror /dev/sdc1

For every ocrconfig or ocrcheck command a trace file to $CRS_Home/log//client directory is written. Below an example from the successful ocrconfig -replace ocr command.

Oracle Database 10g CRS Release 10.2.0.4.0 Production Copyright 1996, 2008 Oracle. All rights reserved.
2008-08-06 07:07:10.424: [ OCRCONF][3086866112]ocrconfig starts...
2008-08-06 07:07:11.328: [ OCRCONF][3086866112]Successfully replaced OCR and set block 0
2008-08-06 07:07:11.328: [ OCRCONF][3086866112]Exiting [status=success]...

Now run ocrcheck to verify if the OCR is pointing to the block device and no error is returned.
Status of Oracle Cluster Registry is as follows :

Version : 2
Total space (kbytes) : 497776
Used space (kbytes) : 3844
Available space (kbytes) : 493932
ID : 576761409
Device/File Name : /dev/sdb1
Device/File integrity check succeeded
Device/File Name : /dev/sdc2
Device/File integrity check succeeded

Cluster registry integrity check succeeded

Method 2 (Offline)

In place method when additional storage is not available, but this requires cluster downtime.

Below the existing mapping from the raw bindings to the block devices, is defined in /etc/sysconfig/rawdevices

/dev/raw/raw1 /dev/sdb1
/dev/raw/raw2 /dev/sdc1

# raw -qa
/dev/raw/raw1: bound to major 8, minor 17
/dev/raw/raw2: bound to major 8, minor 33

# ls –ltra /dev/raw/raw*
crw-r----- 1 root oinstall 162, 1 Jul 24 10:39 /dev/raw/raw1
crw-r----- 1 root oinstall 162, 2 Jul 24 10:39 /dev/raw/raw2

# ls -ltra /dev/*
brw-r----- 1 root oinstall 8, 17 Jul 24 10:39 /dev/sdb1
brw-r----- 1 root oinstall 8, 33 Jul 24 10:39 /dev/sdc1

1. Shutdown Oracle Clusterware on all nodes using "crsctl stop crs" as root. 

2. On all nodes run the following commands as root:

# ocrconfig -repair ocr /dev/sdb1
# ocrconfig -repair ocrmirror /dev/sdc1

3. On one node as root run:

# ocrconfig -overwrite

In the $CRS_Home/log//client directory there is a trace file from "ocrconfig -overwrite" like ocrconfig_.log which should exit with status=success like below:

cat /crs/log/node1/client/ocrconfig_20022.log

Oracle Database 10g CRS Release 10.2.0.4.0 Production Copyright 1996, 2008 Oracle. All rights reserved.
2008-08-06 06:41:29.736: [ OCRCONF][3086866112]ocrconfig starts...
2008-08-06 06:41:31.535: [ OCRCONF][3086866112]Successfully overwrote OCR configuration on disk
2008-08-06 06:41:31.535: [ OCRCONF][3086866112]Exiting [status=success]...

As a verification step run ocrcheck on all nodes and the Device/File Name should reflect the block devices replacing the raw devices:

# ocrcheck
Status of Oracle Cluster Registry is as follows :
Version : 2
Total space (kbytes) : 497776
Used space (kbytes) : 3844
Available space (kbytes) : 493932
ID : 576761409
Device/File Name : /dev/sdb1
Device/File integrity check succeeded
Device/File Name : /dev/sdc1
Device/File integrity check succeeded

Cluster registry integrity check succeeded

Example of adding an OCR device file on raw device

If you have upgraded your environment from a previous version, where you only had one OCR device file, you can use the following step to add an OCRMIRROR file. 

Add /dev/raw/raw2 as OCR mirror device 

# ocrconfig -replace ocrmirror /dev/raw/raw2

Example of adding/replacing OCR/OCRMIRROR on cluster file system 

The new OCR/OCRMIRROR file on the cluster filesystem must exist before add/replace can happen. For example, the new OCR and OCRMIRROR will be located under:
/cluster_fs/OCR/newocr.dat
/cluster_fs/OCR/newocrm.dat

As root user:
# touch /cluster_fs/OCR/newocr.dat
# touch /cluster_fs/OCR/newocrm.dat
# chown root:oinstall /cluster_fs/OCR/newocr.dat
# chown root:oinstall /cluster_fs/OCR/newocrm.dat
# chmod 640 /cluster_fs/OCR/newocr.dat
# chmod 640 /cluster_fs/OCR/newocrm.dat

To add OCRMIRROR:
# ocrconfig -replace ocrmirror /cluster_fs/OCR/newocrm.dat

To replace OCR or OCRMIRROR:
# ocrconfig -replace ocr /cluster_fs/OCR/newocr.dat
# ocrconfig -replace ocrmirror /cluster_fs/OCR/newocrm.dat

ADD/DELETE/MOVE Voting Disk

Note: 1. crsctl votedisk commands must be run as root
2 .If the new voting disk is on cluster file system, then it needs to be touched with proper ownership and permission before they can be added. 
3. If the old voting disk is on cluster file system, it needs to be deleted manually after crsctl delete css votedisk command.
4. The voting disk must be owned by the oracle user, in the oinstall group, and must have permissions set to 644. In 10g provide at least 20 MB disk space for the voting disk. In 11g provide at least 280 MB disk space for the voting disk.

10.2 (all versions)

Shutdown the Oracle Clusterware (crsctl stop crs as root) on all nodes before making any modification to the voting disk. Determine the current voting disk location using:
crsctl query css votedisk

1. To add a Voting Disk, provide the full path including file name: 

# crsctl add css votedisk -force

2. To delete a Voting Disk, provide the full path including file name:

# crsctl delete css votedisk -force

3. To move a Voting Disk, provide the full path including file name:

# crsctl add css votedisk –force
# crsctl delete css votedisk –force

After modifying the voting disk, start the Oracle Clusterware stack on all nodes

# crsctl start crs

Verify the voting disk location using 

# crsctl query css votedisk

11.1.0.6 and onwards

Starting with 11.1 onwards the below commands can be performed online.

1. To add a Voting Disk, provide the full path including file name:

# crsctl add css votedisk

2. To delete a Voting Disk, provide the full path including file name:

# crsctl delete css votedisk

3. To move a Voting Disk, provide the full path including file name:

# crsctl add css votedisk  
# crsctl delete css votedisk  

Verify the voting disk location using:

# crsctl query css votedisk

EXAMPLE MOVING VOTING DISK FROM RAW DEVICE to BLOCK DEVICE

In this example the voting disks will be on the following devices:

/dev/raw/raw4
/dev/raw/raw5
/dev/raw/raw6

Backup Voting before starting any modification. 

To determine the configured voting devices run "crsctl query css votedisk"

# crsctl query css votedisk
0. 0 /dev/raw/raw4
1. 0 /dev/raw/raw5
2. 0 /dev/raw/raw6
located 3 votedisk(s).

Backup Voting

Take a backup of all voting disk:

$ dd if=voting_disk_name f=backup_file_name

For Windows:

ocopy \\.\votedsk1 o:\backup\votedsk1.bak

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 f=voting_disk_name

Moving Voting Device from RAW Device to Block Device

1) Run crsctl query css votedisk to determine the current voting disks:

# crsctl query css votedisk
0. 0 /dev/raw/raw4
1. 0 /dev/raw/raw5
2. 0 /dev/raw/raw6
located 3 votedisk(s).

2) Shutdown Oracle Clusterware on all nodes using  "crsctl stop crs" as root.

Note: This step is only required for 10g CRS. For 11.1 this is an online operation and no cluster outage is required.

3) Perform. add new voting disk and delete old voting disk. Please note, it is not allowed to delete the last defined voting disk without adding a new one first. Perform. the below commands on one node only:

# crsctl delete css votedisk /dev/raw/raw4 -force
# crsctl add css votedisk /dev/vote1 -force
# crsctl delete css votedisk /dev/raw/raw5 -force
# crsctl delete css votedisk /dev/raw/raw6 -force
# crsctl add css votedisk /dev/vote2 -force
# crsctl add css votedisk /dev/vote3 –force

4) Verify with crsctl query css votedisk:

# crsctl query css votedisk
0. 0 /dev/vote1
1. 0 /dev/vote2
2. 0 /dev/vote3 
located 3 votedisk(s).

5) After this the Oracle Clusterware stack can be restarted with  "crsctl start crs" as root. (Only required for 10g CRS)

Monitoring the cluster_alert.log in $CRS_HOME/log//alertnode.log the new configured voting disks should be online:

2008-08-06 07:41:55.029
[cssd(31750)]CRS-1605:CSSD voting file is online: /dev/vote1. Details in /crs/log/node1/cssd/ocssd.log.
2008-08-06 07:41:55.038
[cssd(31750)]CRS-1605:CSSD voting file is online: /dev/vote2. Details in /crs/log/node1/cssd/ocssd.log.
2008-08-06 07:41:55.058
[cssd(31750)]CRS-1605:CSSD voting file is online: /dev/vote3. Details in /crs/log/node1/cssd/ocssd.log.
[cssd(31750)]CRS-1601:CSSD Reconfiguration complete. Active nodes are node1 node2 .

References

NOTE:390880.1 - OCR Corruption after Adding/Removing voting disk to a cluster when CRS stack is running
NOTE:866102.1 - Renaming OCR Using "ocrconfig -overwrite" Fails

来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/7419833/viewspace-713123/，如需转载，请注明出处，否则将追究法律责任。

转载于:http://blog.itpub.net/7419833/viewspace-713123/