OCR and Voting Disk Recovery

OCR and Voting
Disk Recovery
Step #1 Stop cluster on each node (Root user).
# crsctl stop crs -f
Step #2 we are starting the cluster in the
excusive mode (Root user)
As root start
GI in exclusive mode on one node only:
In 11201 RAC,
we have to use below option to start the cluster in the exclusive mode.
# crsctl start crs -excl
In 11202 RAC,
we have to use below option to start the cluster in the exclusive mode.
# crsctl start crs -excl -nocrs
Note: A new
option ‘-nocrs‘ has been introduced with 
11.2.0.2, which prevents the start of the ora.crsd resource. It is vital
that this option is specified; otherwise the failure to start the ora.crsd
resource will tear down ora.cluster_interconnect.haip, which in turn will cause
ASM to crash.
If you don’t
have the OCR DISK GROUP, then we need to create the disk group else move to
restoring OCR DISK
Step #3 Restoring OCR
To Know the
OCR Location on the cluster environment
$ cat /etc/oracle/ocr.loc 
— In Linux
To Check whether
ocrcheck is corrupted or not
# ocrcheck
Check whether
ocrcheck is able to complete it successfully
OCR CHECK Ex
# ocrcheck
Status of Oracle Cluster Registry is as follows :
        
Version                  :          3
         Total
space (kbytes)     :     262120
         Used space
(kbytes)      :       4404
         Available
space (kbytes) :     257716
         ID                       : 1306201859
        
Device/File Name         :  +DG01
                                    Device/File
integrity check succeeded
                                    Device/File
not configured
                                    Device/File
not configured
                                    Device/File
not configured
                                    Device/File
not configured
         Cluster
registry integrity check succeeded
         Logical
corruption check succeeded
       
Note: 1) Check
whether cluster registry integrity check is successful.
          2) When you run as root user, logical
corruption check will be bypassed.
If you run as
oracle user, you can see this line end of the “ocrcheck” output.
“Logical
corruption check bypassed due to non-privileged user”
To Know the OCR Location on the cluster
environment
$ cat /etc/oracle/ocr.loc  — In Linux
If the OCR
DISK corrupted, then perform the below steps
Locate OCR LOG file location
$ORACLE_HOME
/log/<hostname>/client/ocrcheck_<pid>.log
Locate the latest automatic OCR backup
$GRID_HOMEbinocrconfig –showbackup
Restore the latest OCR backup(root user)
# ocrconfig -restore $ORACLE_HOME/cdata/testdbrac1/backup00.ocr
Step #4 Recreating
Voting Disk
Recreate the
Voting file (root user)
The Voting
file needs to be initialized in the CRS disk group
# crsctl replace votedisk +DG01
Note: 1) Above
command will Re-create/move your voting disk in the specified ASM Disk Group,
if you query the voting disk it will display your voting disk location in the
DISK Group which has been specified above.
2)  Voting File is  no longer supported to take a manual backup
of it with dd.  Instead, the Voting File
gets backed up automatically into the OCR.
Query Voting Disk location
# $ORACLE_HOME/bin/crsctl query css votedisk
Note: You
cannot create more than 1 voting disk in the same or on another/different Disk
group disk when using External Redundancy in 11.2. The rules are as follows:
External = 1
voting disk
Normal= 3
voting disk
High= 5 voting
disk
Step #5 Stop & start the cluster
Shutdown CRS è
CRS is running in exclusive mode, it needs to be shutdown (Root User).
# crsctl stop crs
Start CRS è
Start the CRS in one node, if everything is ok then start the CRS in other
nodes (root user).
# crsctl start crs
CRS Status è
Once started, you can check the status of the CRS(Root / Oracle user)
# crsctl stat res –t –init     
# crsctl check cluster –all
# $ORACLE_HOME/bin/crsctl status resource –t
Important Tips
1) Oracle
Clusterware 11g Release 2 backs up the OCR automatically every four hours on a
schedule that is dependent on when the node started
4-hour backups
(3 max) –backup00.ocr, backup01.ocr, and backup02.ocr.
Daily backups
(2 max) – day.ocr and day_.ocr
Weekly backups
(2 max) – week.ocr and week_.ocr
You can use
the ocrconfig command to view the current OCR backups as seen in this
Ocrconfig
–showbackup auto
Note:
automatic backups will not occur, when the cluster is down
2) Verifying
OCR integrity of entire cluster nodes by running CVU command:
$ cluvfy comp ocr -n all –verbose

3) Oracle
Local Repository (OLR), this repository designed to store information and
profiles for local resources, resources that dedicated to particular node. It
improves the performance of accessing local resources profile information,
redundancy and manageability. In Grid Infrastructure RAC configuration there is
usual one global shared OCR and OLR’s on each node. In Oracle Restart
environment there is only OLR repository. In 11g R2 there is also new feature,
Grid Plug and Play (GPNP), as the name implies, it helps to automate and
simplify some of the aspects of grid administration. GPNP maintains profile, it
is XML file that stores the configuration information of some components
maintained by GPNP, for example vips and interconnect information is stored
here.
  • April 8, 2015 | 41 views
  • Comments