在Oracle10g RAC环境中，OCR及Voting Disk对于集群来说都是非常重要的。
那么如何对两者进行备份并且能够在故障时进行恢复就显得极为重要。
OCR的数据Oracle会自动执行备份，通过ocrconfig -showbackup命令可以查看这些备份：
bash-2.05$ ocrconfig -showbackup
db490-9 2008/03/01 19:26:29 /opt/oracle/product/10.2.0/crs10g/cdata/crs
db490-9 2008/03/01 15:26:29 /opt/oracle/product/10.2.0/crs10g/cdata/crs
db490-9 2008/03/01 11:26:29 /opt/oracle/product/10.2.0/crs10g/cdata/crs
db490-9 2008/02/29 03:26:26 /opt/oracle/product/10.2.0/crs10g/cdata/crs
db490-9 2008/02/22 03:26:13 /opt/oracle/product/10.2.0/crs10g/cdata/crs
bash-2.05$ hostname
db480-5 |
注意这个备份只会存储在一个节点上，并非所有节点都会记录这个备份。
在备份节点的相应目录下我们可以找到这些备份：
$ cd /opt/oracle/product/10.2.0/crs10g/cdata/crs
$ ls -al
total 66420
drwxrwxr-x 2 oracle dba 512 Mar 1 19:26 .
drwxrwxr-x 4 oracle dba 512 Nov 23 16:39 ..
-rw-r--r-- 1 root root 4845568 Mar 1 19:26 backup00.ocr
-rw-r--r-- 1 root root 4845568 Mar 1 15:26 backup01.ocr
-rw-r--r-- 1 root root 4845568 Mar 1 11:26 backup02.ocr
-rw-r--r-- 1 root root 4845568 Feb 29 03:26 day.ocr
-rw-r--r-- 1 root root 4845568 Mar 1 03:26 day_.ocr
-rw-r--r-- 1 root root 4845568 Feb 22 03:26 week.ocr
-rw-r--r-- 1 root root 4845568 Feb 29 03:26 week_.ocr |
当出现故障时，可以通过ocrconfig命令来执行恢复，通过帮助可以看到详细的用法：
$ ocrconfig -help
Name:
ocrconfig - Configuration tool for Oracle Cluster Registry.
Synopsis:
ocrconfig [option]
option:
-export <filename> [-s online]
- Export cluster register contents to a file
-import <filename> - Import cluster registry contents from a file
-upgrade [<user> [<group>]]
- Upgrade cluster registry from previous version
-downgrade [-version <version string>]
- Downgrade cluster registry to the specified version
-backuploc <dirname> - Configure periodic backup location
-showbackup - Show backup information
-restore <filename> - Restore from physical backup
-replace ocr|ocrmirror [<filename>] - Add/replace/remove a OCR device/file
-overwrite - Overwrite OCR configuration on disk
-repair ocr|ocrmirror <filename> - Repair local OCR configuration
-help - Print out this help information
Note:
A log file will be created in
$ORACLE_HOME/log/<hostname>/client/ocrconfig_<pid>.log. Please ensure
you have file creation privileges in the above directory before
running this tool. |
如果不出意外，恢复过程将会很简单，通过 ocrconfig -restore 就可以回复这里的物理备份。
对于voting disk可以通过dd来进行备份。
首先通过 crsctl query css votedisk 命令可以找到voting disk的存储地：
bash-2.05$ crsctl query css votedisk
0. 0 /dev/rdsk/voting
located 1 votedisk(s).
|
然后通过dd备份：
bash-2.05$ dd if=/dev/rdsk/voting of=voting.bak
211456+0 records in
211456+0 records out
bash-2.05$ ls -al
total 211588
drwxr-xr-x 2 oracle dba 512 Mar 1 21:13 .
drwxr-xr-x 11 oracle dba 512 Jan 25 17:59 ..
-rw-r--r-- 1 oracle dba 108265472 Mar 1 21:14 voting.bak |
当需要恢复时，通过dd进行恢复即可。这个voting disk记录了什么内容呢？
通过strings可以将其中的字符串取出来看一个印象：
bash-2.05$ strings voting.bak |sort -u
CLSf
Vote
cLssTock
clSs0pEr
clsSkilL
db480-5
db490-9
z{|} |
|
