解析OCR與Voting Disk以及其管理
Voting Disk和OCR是Oracle Clusterware的2部分。Voting Disk里面記錄著節點成員的信息。如RAC數據庫中有哪些節點成員，節點增加或者刪除時也同樣會將信息記錄進來。Voting Disk必須存放在共享存儲上，通常來說是存放在裸設備上。為了保證Voting Disk的安全，需要配置多個Voting Disk，Oracle建議Voting Disk的個數應該為奇數個，如 1、3、5個，每個Voting Disk的大小約為20MB。
OCR 記錄的是節點成員的配置信息，如數據庫、ASM、實例、監聽器、VIP等CRS資源的配置信息。CRS進程管理的信息來自OCR的內容。OCR存儲的配置信息是以目錄樹的形式來記錄一系列“鍵-值”對應信息的。OCR記錄著 CRS進程管理資源的所有配置信息。大小約為100MB。
對Voting Disk的更改必須用root來進行。
添加一個Voting Disk成員：crsctl add css votedisk /dev/raw/raw3'
刪除一個Voting Disk成員：crsctl delete css votedisk /dev/raw/raw3'
對OCR的增加、刪除和替代配置可以由root用戶通過ocrconfig -replace來操作：
ocrconfig -replace /dev/raw/raw1
注意：增加、刪除Voting Disk及恢復Voting Disk和OCR時，RAC中的所有資源都必須停止。
Voting Disk和OCR存放的信息是至關重要的，一旦他們丟失或者損壞的話，Clusterware將無法啟動，這樣整個RAC都無法啟動。因此需要對Voting Disk和OCR進行完備的備份。
對Voting Disk的備份操作可以通過dd命令來操作。
查看位置：
#crsctl query css votedisk
備份操作：
#dd if=/dev/raw/raw2 f=/home/oracle/voting_disk.bak
恢復操作：
#dd if=/home/oracle/voting_disk.bak f=/dev/raw/raw2
默認情況下，RAC會在其中一個節點上每4個小時都自動備份一次OCR。并保留最近的3次備份，另外還保留最近兩天以及最近兩個周末的備份。這個可以通過命令ocrconfig -showbackup來查看。OCR默認的備份路徑為$CRS_HOME/cdata/crs。可以通過ocrconfig -backuploc來更改OCR的備份路徑。OCR自動備份的時間間隔無法修改。我們還可以通過ocrconfig -export 來到處OCR的內容，也可以通過通過ocrconfig -import導入OCR的內容。
可以用ocrconfig -restore 命令對OCR進行恢復。
./ocrconfig -restore /u01/oracle/product/10g/crs/cdata/crs/backup00.ocr
添加Voting Disk:
- [root@rhel1 bin]#./crsctl add css votedisk /u01/ocfs2fs/vdisk2
- Cluster is not in a ready state for online disk addition
- [root@rhel1 bin]#./crsctl add css votedisk /u01/ocfs2fs/vdisk2-force
- Now formatting voting disk: /u01/ocfs2fs/vdisk2
- successful addition of votedisk /u01/ocfs2fs/vdisk2. chown oracle:oinstall /u01/ocfs2fs/vdisk2
- chmod 775 /u01/ocfs2fs/vdisk2
- [root@rhel1 bin]# /etc/init.crs start
- [root@rhel1 bin]#./crsctl query css votedisk
- 0. 0 /u01/ocfs2fs/vdisk
- 1. 0 /u01/ocfs2fs/vdisk2
注意：add voting disk必須是所有服務都關閉的情況下完成。
#p#
添加OCR鏡像:
- [root@rhel1 bin]# touch /u01/ocfs2fs/ocr2
- [root@rhel1 bin]#./ocrconfig -replace ocrmirror /u01/ocfs2fs/ocr2
- [root@rhel1 bin]#./ocrcheck
- Status of Oracle Cluster Registry is as follows :
- Version : 2
- Total space (kbytes) : 262120
- Used space (kbytes) : 2756
- Available space (kbytes) : 259364
- ID : 2062708016
- Device/File Name : /u01/ocfs2fs/ocr
- Device/File integrity check succeeded
- Device/File Name : /u01/ocfs2fs/ocr2
- Device/File integrity check succeeded
- Cluster registry integrity check succeeded
注意：add ocr可以是在線完成。
刪除OCR鏡像:
- [root@rhel1 bin]#./ocrconfig -replace ocrmirror
- [root@rhel1 bin]#./ocrcheck
- Status of Oracle Cluster Registry is as follows :
- Version : 2
- Total space (kbytes) : 262120
- Used space (kbytes) : 2756
- Available space (kbytes) : 259364
- ID : 2062708016
- Device/File Name : /u01/ocfs2fs/ocr
- Device/File integrity check succeeded
- Device/File not configured
- Cluster registry integrity check succeeded
- [root@rhel1 bin]#cat /etc/oracle/ocr.loc
- #Device/file /u01/ocfs2fs/ocr2 being deleted
- ocrconfig_loc=/u01/ocfs2fs/ocr
刪除Voting Disk:
- [root@rhel1 bin]#./crsctl delete css votedisk /u01/ocfs2fs/vdisk2
- Cluster is not in a ready state for online disk removal
- [root@rhel1 bin]#./crsctl stop crs
- Stopping resources. This could take several minutes.
- Successfully stopped CRS resources.
- Stopping CSSD.
- Shutting down CSS daemon.
- Shutdown request successfully issued.
- [root@rhel1 bin]# ./crsctl delete css votedisk /u01/ocfs2fs/vdisk2
- Cluster is not in a ready state for online disk removal
- [root@rhel1 bin]#./crsctl delete css votedisk /u01/ocfs2fs/vdisk2-force
- successful deletion of votedisk /u01/ocfs2fs/vdisk2.
- [root@rhel1 bin]#./crsctl query css votedisk
- 0. 0 /u01/ocfs2fs/vdisk
- located 1 votedisk(s).
#p#
備份、恢復Voting Disk：
- [root@rhel1 bin]#./crsctl check crs
- Failure 1 contacting CSS daemon
- Cannot communicate with CRS
- Cannot communicate with EVM
- [root@rhel1 bin]# dd if=/u01/ocfs2fs/vdisk f=/home/oracle/vdisk_bak //備份,ocfs2也可直接copy
- 20000+0 records in
- 20000+0 records out
- 10240000 bytes (10 MB) copied, 0.301106 seconds, 34.0 MB/s
- [root@rhel1 bin]# rm -rf /u01/ocfs2fs/vdisk
- [root@rhel1 bin]#dd if=/home/oracle/vdisk_bak f=/u01/ocfs2fs/vdisk //恢復,ocfs2也可直接copy
- 20000+0 records in
- 20000+0 records out
- 10240000 bytes (10 MB) copied, 0.173678 seconds, 59.0 MB/s
- [root@rhel1 bin]# chown oracle:oinstall /u01/ocfs2fs/vdisk
- [root@rhel1 bin]# chmod 775 /u01/ocfs2fs/vdisk
- [root@rhel1 bin]#/etc/init.d/init.crs start
- Startup will be queued to init within 30 seconds.
- [root@rhel1 bin]#./crsctl check crs
- CSS appears healthy
- CRS appears healthy
- EVM appears healthy
備份、恢復OCR：
- [root@rhel1 bin]# ./crsctl stop crs
- Stopping resources. This could take several minutes.
- Successfully stopped CRS resources.
- Stopping CSSD.
- Shutting down CSS daemon.
- Shutdown request successfully issued.
- [root@rhel1 bin]# cat /etc/oracle/ocr.loc
- #Device/file /u01/ocfs2fs/ocr2 being deleted
- ocrconfig_loc=/u01/ocfs2fs/ocr
- local_only=false
- [root@rhel1 bin]# mv /u01/ocfs2fs/ocr /u01/ocfs2fs/ocr_bak
- [root@rhel1 crs_1]# cd cdata
- [root@rhel1 cdata]# cd crs
- [root@rhel1 crs]# ll
- total 23144
- -rwxrwxr-x 1 oracle dba 3514368 Mar 1 11:00 13968559
- -rwxrwxr-x 1 oracle dba 3514368 Mar 1 07:00 33426182
- -rw-r--r-- 1 root root 3182592 Mar 8 15:17 34809936
- -rwxrwxr-x 1 oracle dba 3514368 Feb 27 09:38 backup00.ocr
- -rwxrwxr-x 1 oracle dba 3514368 Feb 8 06:02 backup01.ocr
- -rwxrwxr-x 1 oracle dba 2142208 Nov 8 19:25 backup02.ocr
- -rwxrwxr-x 1 oracle dba 2142208 Nov 8 19:25 day.ocr
- -rwxrwxr-x 1 oracle dba 2142208 Nov 8 19:25 week.ocr
- [root@rhel1 crs]# cd ../../bin
- [root@rhel1 bin]# ./ocrconfig -restore /u01/app/oracle/crs_1/cdata/crs/backup02.ocr
- PROT-16: Internal Error
- [root@rhel1 bin]#touch /u01/ocfs2fs/ocr
- [root@rhel1 bin]#./ocrconfig -restore /u01/app/oracle/crs_1/cdata/crs/backup02.ocr
- [root@rhel1 bin]# ./crsctl start crs
- Attempting to start CRS stack
- The CRS stack will be started shortly
- [root@rhel1 bin]# ./crsctl check crs
- CSS appears healthy
- CRS appears healthy
- EVM appears healthy
查看和改變自動備份目錄的命令如下：
./ocrconfig -showbackup //查看自動備份。
./ocrconfig -backuploc
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