Oracle RAC 12.2 CDB rman备份异机恢复到12.2单实例环境

适用范围

建议 12.2.0.1 及以上版本使用

方案概述

Oracle rac 12.2 cdb环境的rman备份需要恢复到12.2单实例环境上进行测试使用，不完全恢复即可，备份在源端和目标端都配置了共享nfs，挂载的路径分别为/rac/rman/test1和/baktmp/rman/test1。源端每周日进行0级全量备份，周一到周六进行1级增量备份

实施步骤

1.查看备份脚本

– 全量备份脚本

$ cat rman_0_level_full.sh
#!/bin/sh
source /home/oracle/.bash_profile
export ORACLE_SID=test1
DAY_TAG=`date +"%Y-%m-%d"`
backdir1=/rac/rman/test1
rman target / nocatalog msglog /rac/rman/test1/log/fullback_$DAY_TAG.log catalog start with '/baktmp/rman/test1';
RMAN> crosscheck backup;
RMAN> delete noprompt expired backup;


2.4.恢复数据文件

$ cat restore.sh
#!/bin/sh
rman target / log=/home/oracle/rman_restore.log alter database disable thread 2;
SQL> alter database drop logfile group 5;
SQL> alter database drop logfile group 6;
SQL> alter database drop logfile group 7;
SQL> alter database drop logfile group 9;


2.9.启动监听并注册本地监听

$ lsnrctl start
$ sqlplus / as sysdba
SQL> alter system set local_listener='(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.10.8)(PORT=1521))';
SQL> alter system register;


2.10.修改max_string_size为extend

$ sqlplus / as sysdba
SQL> alter system set max_string_size = extended scope=spile;
SQL> shut immeidate;
SQL> startup;
SQL> alter pluggable database all open;
SQL> alter pluggable database all save state;


上面sql拼接生成的rename的文本,可以拿过来执行进行rename操作

3.遇到问题

3.1.启动nomount报错

startup nomount pfile='/data/oracle/product/12.2.0.1/dbhome_1/dbs/inittest.ora';
ORA-00371: not enough shared pool memory, should be at least 503735201 bytes


inittest.ora参数文件添加shared_pool_size=5368709120 后重启到nomount

shared_pool_size=5368709120


3.2.权限不足无法找到备份文件

RMAN> restore controlfile from '/baktmp/rman/TEST1/ctl_TEST_20240408_1165174769_27019_1';

RMAN>


赋权限解决

# cd /baktmp/rman/test1
# chmod 777 *20240407* *20240408*


3.3.ORA-00723

RMAN> alter database mount;

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of sql statement command at 04/08/2024 16:39:38
ORA-00723: Initialization parameter COMPATIBLE must be explicitly set


inittest.ora参数文件添加compatible=‘12.2.0.1.0’ 后重启到mount

compatible='12.2.0.1.0'


3.4.ORA-65093

SQL> startup mount;
ORACLE instance started.

Total System Global Area 5536480720 bytes
Fixed Size 19525072 bytes
Variable Size 5435817984 bytes
Database Buffers 67108864 bytes
Redo Buffers 14028800 bytes
ORA-65093: multitenant container database not set up properly


inittest.ora参数文件添加enable_pluggable_database=true 后重启到mount

enable_pluggable_database=true


3.5.恢复日志中找备份文件先报错后failover路径成功

channel c4: errors found reading piece handle=/rac/rman/test1/full_TEST_20240407_1165096836_27003_1
channel c4: failover to piece handle=/baktmp/rman/test1/full_TEST_20240407_1165096836_27003_1 tag=TAG20240407T220049
channel c4: restored backup piece 1
channel c4: restore complete, elapsed time: 03:49:23


恢复之前执行crosscheck可以解决此报错

RMAN> crosscheck backup;


3.6.启动pdb报错

ORA-14694: database must in UPGRADE mode to begin MAX_STRING_SIZE migration


由于rman恢复的时候备份集中已经包含utl32k.sql脚本的结果了,所以只需要修改 max_string_size 参数为extended后重启即可,参数默认值是standard

$ sqlplus / as sysdba
SQL> alter system set max_string_size = extended scope=spile;
SQL> shut immeidate;
SQL> startup;
SQL> alter pluggable database all open;


4.其他说明

CONFIGURE RETENTION POLICY TO RECOVERY WINDOW OF 60 DAYS;


rman保留备份60天的策略对于pdbseed不适用,目前发现每次全量备份完毕会删除上次全备份生成的pdbseed备份片,可能和pdb$seed是read only的有关,具体没细究