RAC数据库恢复到单实例数据库的基本步骤如下:
a.准备单实例服务器,pfile文件,启动到nomount
b.备份rac数据库
c.将备份文件拷贝到单实例服务器
d.在单实例服务器上还原、恢复
e.resetlogs打开数据库
f.rename redo文件名
g.disable thread 2并删除其redo组
h.增加temp临时表空间数据文件
i.删除不必要的undo表空间
业务需要(比如,测试备份)将RAC数据库通过备份恢复到单实例服务器;下面是实际操作步骤;测试环境:RHEL4u7、oracle 10gR2、ASM、2节点,单实例服务器:RHEL4u7、oracle 10gR2、文件系统;在测试环境下,RAC 数据库文件都在asm时,在rename file操作时会遇到了BUG问题,最后的恢复时则需要重建控制文件;上面介绍的步骤是指没有BUG的情况的操作;
另外,备份、拷贝的环节就请参考其他文档,就不介绍了,下面从第4步在单实例服务器上还原、恢复与打开开始介绍;
RMAN> startup nomount RMAN> restore controlfile to '/app/oracle/oradata/ctl01.dbf' from '/app/oracle/backup/ctl_23_1_855331400'; RMAN> run{startup mount; set until sequence 870 thread 1; set newname for datafile 1 to '/app/oracle/oradata/system.257.779207027'; set newname for datafile 3 to '/app/oracle/oradata/sysaux.262.779207043'; set newname for datafile 4 to '/app/oracle/oradata/users.260.779207053'; set newname for datafile 2 to '/app/oracle/oradata/undotbs1.264.779207043'; set newname for datafile 15 to '/app/oracle/oradata/pptest_tbs.282.793979093'; set newname for datafile 5 to'/app/oracle/oradata/undotbs2.268.779207507'; set newname for datafile 8 to'/app/oracle/oradata/tbs_p3w.271.780396123'; set newname for datafile 9 to'/app/oracle/oradata/tbs_p4w.274.780396125'; set newname for datafile 6 to'/app/oracle/oradata/tbs_p1w.270.780396121'; set newname for datafile 7 to'/app/oracle/oradata/tbs_p2w.273.780396123'; set newname for datafile 14 to'/app/oracle/oradata/pptest_tbs.279.781454807'; restore database; switch datafile all; recover database; } sys@racdb3> alter database rename file '+DG/racdb/onlinelog/group_1.263.779207025' to '/app/oracle/oradata/redo1.log'; |
rename 完所有redo文件后,即可resetlogs打开数据库;但是,实际操作中遇到bug7207932:Rman Restore From RAC ASM To Single Instance Non ASM Fails With ORA-00600 [kgeade_is_0] (文档 ID 1146703.1)
Bug 7207932 ORA-600 [KGEADE_IS_0] WHEN RENAMING A FILE FROM ASM TO FS
要想绕开的方法则是重建控制文件后,再打开数据库
sys@racdb3> alter database backup controlfile to trace as '/tmp/ctl.trc' reuse resetlogs;