11g备库无法开启ADG的原因分析 (r7笔记第62天)

今天碰到一个有些奇怪的问题，但是奇怪的现象背后都是有本质的因果。 下午在做一个环境的检查时，发现备库是在mount阶段，这可是一个11gR2的库，没有ADG实在是太浪费了，对于这种情况感觉太不应该了。 所以尝试启动至open阶段，发现状态一直是read only,在ADG中应该是READ ONLY WITH APPLY才对啊。 使用dg broker设置为READ-ONLY,备库的数据库日志如下： Standby Database: stestdb3, Enabled Physical Standby (0x02010000) 08/14/2014 16:03:28 version check on database stestdb3 detected stale metadata, requesting update from primary database Creating process RSM0 12/29/2015 16:28:11 Command EDIT DATABASE stestdb3 SET STATE = READ-ONLY completed Read-Only state no longer supported 12/29/2015 16:29:10 似乎也看不出来什么端倪。使用dg broker查看一下。发现报了下面的错误。 DGMGRL> show configuration; Configuration - testdb Protection Mode: MaxPerformance Databases: testdbbak93 - Primary database stestdb3 - Physical standby database Error: ORA-16766: Redo Apply is stopped Fast-Start Failover: DISABLED Configuration Status: ERROR 查看dg broker的日志如下： Data Guard Broker initializing... Data Guard Broker initialization complete Tue Dec 29 16:47:15 2015 SMON: enabling cache recovery No Resource Manager plan active Physical standby database opened for read only access. Completed: alter database open Tue Dec 29 16:47:16 2015 idle dispatcher 'D000' terminated, pid = (18, 1) Tue Dec 29 16:51:40 2015 Primary database is in MAXIMUM PERFORMANCE mode RFS[3]: Assigned to RFS process 3596 RFS[3]: Selected log 7 for thread 1 sequence 72606 dbid -1549369665 branch 746558785 Tue Dec 29 16:51:41 2015 RFS[4]: Assigned to RFS process 3590 RFS[4]: Selected log 8 for thread 1 sequence 72605 dbid -1549369665 branch 746558785 Tue Dec 29 16:51:42 2015 Archived Log entry 69432 added for thread 1 sequence 72605 ID 0xa829ec3b dest 2: 从上面的情况可以很明显看到，确实MRP没有开始工作，只有RFS在接收归档。 然后使用dg broker把备库设置为ONLINE状态，再次查看dg broker的检查，发现检查就没有问题了。 DGMGRL> show configuration; Configuration - testdb Protection Mode: MaxPerformance Databases: testdbbak93 - Primary database stestdb3 - Physical standby database Fast-Start Failover: DISABLED Configuration Status: SUCCESS 总体感觉这不是一个11g的库。 然后再次尝试，手工启动到open阶段，然后可以看到备库还是READ ONLY,重启之后问题依然存在。 对于这个问题，最好的方式也还是查看日志，这个备库是一年前重启的了，庆幸的是数据库日志依然存在。从当时的启动情况来看，也没有其它的错误。 但是我注意到了compatible这个参数，因为在11g的库中还是比较显眼的。所以这个参数引起了我的好奇。 结果带着疑问在MOS一查，果然有几篇相关的文章，看来又碰上一个遗留问题，而且有一个相关的BUG描述。 ACTIVE DATAGUARD (ADG) NOT POSSIBLE WITH COMPATIBLE < 11.1.0.0.0 (Doc ID 1363396.1) BUG:13032521 - ADG PHYSICAL STANDBY GOES TO MOUNT STATE INSTEAD OF READ ONLY WITH APPLY 问题基本定位后，主备库中查看这个参数都是10.2.0.5.0 SQL> show parameter compa NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ compatible string 10.2.0.5.0 那么按照bug描述的WA，是设置备库的compatible为11.1.0.7以上，这个参数的修改需要重启实例，所以还是比较影响的，主库目前是没法重启了。 SQL> alter system set compatible='11.2.0.3.0'; alter system set compatible='11.2.0.3.0' * ERROR at line 1: ORA-02095: specified initialization parameter cannot be modified 现在备库设置一番，先看看行不行。 SQL> alter system set compatible='11.2.0.3.0' scope=spfile; System altered. 重启时，可以看到备库的数据库日志有下面这么一段输出。 Tue Dec 29 17:25:26 2015 Spfile /U01/app/oracle/product/11.2.3/db_1/dbs/spfiletestdb.ora is in old pre-11 format and compatible >= 11.0.0; converting to new H.A.R.D. compliant format. Completed: alter database mount 但是再次设置为ONLINE，查看数据库状态依旧是MOUNT SQL> select open_mode from v$database; OPEN_MODE -------------------- READ ONLY 看来备库修改还不行，主库也得修改一致。 不过查看数据库日志可以看到下面的这么一段内容，发现MRP启动失败。 ALTER DATABASE RECOVER MANAGED STANDBY DATABASE THROUGH ALL SWITCHOVER DISCONNECT USING CURRENT LOGFILE Attempt to start background Managed Standby Recovery process (testdb) Tue Dec 29 17:57:03 2015 MRP0 started with pid=29, OS id=17740 MRP0: Background Managed Standby Recovery process started (testdb) started logmerger process Tue Dec 29 17:57:08 2015 Managed Standby Recovery starting Real Time Apply Parallel Media Recovery started with 16 slaves Waiting for all non-current ORLs to be archived... All non-current ORLs have been archived. Media Recovery Log /U01/app/oracle/fra/StestDB3/archivelog/2015_12_29/o1_mf_1_72606_c84n0xml_.arc Completed: ALTER DATABASE RECOVER MANAGED STANDBY DATABASE THROUGH ALL SWITCHOVER DISCONNECT USING CURRENT LOGFILE Errors with log /U01/app/oracle/fra/StestDB3/archivelog/2015_12_29/o1_mf_1_72606_c84n0xml_.arc MRP0: Background Media Recovery terminated with error 38800 Errors in file /U01/app/oracle/diag/rdbms/stestdb3/testdb/trace/testdb_pr00_17745.trc: ORA-38800: Cannot start Redo Apply on the open physical standby database Managed Standby Recovery not using Real Time Apply Recovery interrupted! MRP0: Background Media Recovery process shutdown (testdb) 看来这个参数变化影响确实不小，备库先恢复正常状态再说，等协调主库重启再处理了，所以开始恢复参数原有的设置。把compatible设置为10.2.0.5.0 ?但是重启的时候就开始报错了。 SQL> alter database mount; alter database mount * ERROR at line 1: ORA-00201: control file version 11.2.0.3.0 incompatible with ORACLE version 10.2.0.5.0 ORA-00202: control file: '/U01/app/oracle/oradata/testdb/control01.ctl' 这个问题看似还有余地，在主库生成备库控制文件，传输过去，mount就没有问题了 主库： SQL> alter database create standby controlfile as '/tmp/std1.ctl'; Database altered. ?备库： SQL> alter database mount standby database; Database altered. 但是这个时候查看备库的数据库日志，发现问题貌似变麻烦了。文件头部已经修改，已经不同步了。 ALTER DATABASE RECOVER managed standby database disconnect from session Attempt to start background Managed Standby Recovery process (testdb) Tue Dec 29 18:28:13 2015 MRP0 started with pid=30, OS id=24283 MRP0: Background Managed Standby Recovery process started (testdb) started logmerger process Tue Dec 29 18:28:18 2015 Managed Standby Recovery not using Real Time Apply Read of datafile '/U01/app/oracle/oradata/testdb/system01.dbf' (fno 1) header failed with ORA-01130 Rereading datafile 1 header failed with ORA-01130 MRP0: Background Media Recovery terminated with error 1110 Errors in file /U01/app/oracle/diag/rdbms/stestdb3/testdb/trace/testdb_pr00_24288.trc: ORA-01110: data file 1: '/U01/app/oracle/oradata/testdb/system01.dbf' ORA-01122: database file 1 failed verification check ORA-01110: data file 1: '/U01/app/oracle/oradata/testdb/system01.dbf' ORA-01130: database file version 11.2.0.3.0 incompatible with ORACLE version 10.2.0.5.0 Slave exiting with ORA-1110 exception Errors in file /U01/app/oracle/diag/rdbms/stestdb3/testdb/trace/testdb_pr00_24288.trc: ORA-01110: data file 1: '/U01/app/oracle/oradata/testdb/system01.dbf' ORA-01122: database file 1 failed verification check ORA-01110: data file 1: '/U01/app/oracle/oradata/testdb/system01.dbf' ORA-01130: database file version 11.2.0.3.0 incompatible with ORACLE version 10.2.0.5.0 Recovery Slave PR00 previously exited with exception 1110 MRP0: Background Media Recovery process shutdown (testdb) Completed: ALTER DATABASE RECOVER managed standby database disconnect from session 对应的trace文件如下： *** 2015-12-29 18:28:18.495 4320 krsh.c Managed Standby Recovery not using Real Time Apply Read of datafile '/U01/app/oracle/oradata/testdb/system01.dbf' (fno 1) header failed with ORA-01130 Rereading datafile 1 header failed with ORA-01130 V10 STYLE FILE HEADER: Compatibility Vsn = 186647296=0xb200300 Db ID=2745597631=0xa3a67ebf, Db Name='testDB' Activation ID=0=0x0 Control Seq=1=0x1, File size=147200=0x23f00 File Number=1, Blksiz=8192, File Type=3 DATA Tablespace #0 - SYSTEM rel_fn:1 对于这种情况，其实恢复备库11g的控制文件，重启主库 应该就可以解决了，但是重启主库还需要协调时间，找维护窗口，所以不是一蹴而就的事情，那么这个期间容灾是重中之重，一旦主库出了问题，影响还是不小，所以最后的无奈之举就是重建备库。 当然搭建备库还是可以采用11g的active方式。 rman target sys@xxxxx auxiliary sys@xxxx nocatalog RMAN> duplicate target database for standby from active database nofilenamecheck; ?然后就没有然后了，就是备库搭建成功了，看着白忙活一场，心中像打翻了五味瓶。