dg搭建后oracle_redo不存在
目的：在oracle 10.2.0.4 环境中，搭建oracle dg遇到 备库redo不存在的问题，另一位同事搭建oracle 11.2.0.4 dg在备库也遇到同样的问题，如下描述处理过程。
参考
处理流程
1.描述
生产环境dg 10.2.0.4,是由RMAN异机恢复，主库存在的redo路径在备库并未提取创建，也并未rename 日志文件，因此recover databaes完毕之后，其余MRP进程，同步应用日志，发现redo备库不存在，如下是操作日志
2.操作
尝试取消mrp
alter database recover managed standby database cancel;
确认dg角色 SQL> select dbid,name, database_role,open_mode,SWITCHOVER_STATUS,FLASHBACK_ON,PROTECTION_MODE,FORCE_LOGGING from v$database; DBID NAME DATABASE_ROLE ----------- ---------- -------------------- 3xx9 WxxxB PHYSICAL STANDBY 参数调整 SQL> alter system set standby_file_management=manual; 查询日志组状态 SQL> select group# ,thread#,bytes/1024/1024,status from v$log; GROUP# THREAD# BYTES/1024/1024 STATUS ---------- ---------- --------------- ---------------- 1 1 1024 CLEARING 2 1 1024 CLEARING 3 1 1024 CLEARING_CURRENT 4 1 1024 CLEARING 5 1 1024 CLEARING 6 1 1024 CLEARING 7 1 1024 CLEARING 8 1 1024 CLEARING 8 rows selected. 手工对日志组进行clear后续进行drop 发现报错！ SQL> ALTER DATABASE CLEAR LOGFILE GROUP 1; alter database drop logfile group 6;
ORA-01624: log 6 needed for crash recovery of instance webdb (thread 1)
ORA-00312: online log 6 thread 1: '/oracle/oradata/redolog/redo6.log'
根据MOS文档，Drop Redo Logs on Standby操作失败！！！
Sync Redo Logs on Primary and Standby 这部分区域存在一句话描述
7. Start Redo Apply:
When using Oracle Database >=10.2.0.1 and LOG_FILE_NAME_CONVERT is configured the online redo logs will
be automatically cleared and physically created when starting recovery.
因此采用上述建议
恢复参数
SQL> alter system set standby_file_management=auto; 设置参数，与主库相同，本次并不做转换 alter system set LOG_FILE_NAME_CONVERT ='/oracle/oradata/redolog/','/oracle/oradata/redolog/' scope=spfile; SQL> startup force mount; 重启dg生效参数
开启mrp进程 SQL>recover managed standby database disconnect from session; 观察db_alert Managed Standby Recovery not using Real Time Apply parallel recovery started with 16 processes Tue Nov 26 22:57:15 2019 Waiting for all non-current ORLs to be archived... Tue Nov 26 22:57:15 2019 Errors in file /oracle/admin/webdb/bdump/webdb_mrp0_13806.trc: ORA-00313: open failed for members of log group 1 of thread 1 ORA-00312: online log 1 thread 1: '/oracle/oradata/redolog/redo1.log' ORA-27037: unable to obtain file status Linux-x86_64 Error: 2: No such file or directory Additional information: 3 Tue Nov 26 22:57:15 2019 操作系统验证-日志存在 [oracle@ytwebdb redolog]$ cd /oracle/oradata/redolog/ [oracle@ytwebdb redolog]$ ls -lrt total 8388672 -rw-r----- 1 oracle dba 1073742336 Nov 26 22:57 redo1.log -rw-r----- 1 oracle dba 1073742336 Nov 26 22:57 redo2.log -rw-r----- 1 oracle dba 1073742336 Nov 26 22:57 redo3.log -rw-r----- 1 oracle dba 1073742336 Nov 26 22:57 redo4.log
