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RAC某节点启动遭遇ORA-01105,ORA-01606

2016-04-14 17:03  AlfredZhao  阅读(...)  评论(...编辑  收藏

环境:RHEL6.5 + Oracle11.2.0.4 双节点RAC
故障现象:节点1实例没有启动成功,节点2正常启动。

1.故障现象

尝试启动RAC 节点1,遭遇ORA-01105,ORA-01606:

SQL> startup mount;
ORACLE instance started.

Total System Global Area 9.4869E+10 bytes
Fixed Size                  2264056 bytes
Variable Size            5.0197E+10 bytes
Database Buffers         4.4560E+10 bytes
Redo Buffers              109174784 bytes
ORA-01105: mount is incompatible with mounts by other instances
ORA-01606: parameter not identical to that of another mounted instance

数据库节点1目前状态是NOMOUNT.

2.解决过程

错误代码说明:

$ oerr ora 1105
01105, 00000, "mount is incompatible with mounts by other instances"
// *Cause:  An attempt to mount the database discovered that another instance
//         mounted a database by the same name, but the mount is not
//         compatible. Additional errors are reported explaining why.
// *Action: See accompanying errors.

$ oerr ora 1606
01606, 00000, "parameter not identical to that of another mounted instance"
// *Cause:  A parameter was different on two instances.
// *Action: Modify the initialization parameter and restart.

查询gc_隐含参数

set linesize 333
col name for a35
col description for a66
col value for a30
SELECT   i.ksppinm name,  
   i.ksppdesc description,  
   CV.ksppstvl VALUE
FROM   sys.x$ksppi i, sys.x$ksppcv CV  
   WHERE   i.inst_id = USERENV ('Instance')  
   AND CV.inst_id = USERENV ('Instance')  
   AND i.indx = CV.indx  
   AND i.ksppinm LIKE '/_gc%' ESCAPE '/'  
ORDER BY   REPLACE (i.ksppinm, '_', '');  

查询结果如下(部分相同值的参数已省略):

--节点1:
_gc_policy_time                     how often to make object policy decisions in minutes               0
_gc_read_mostly_flush_check         if TRUE, optimize flushes for read mostly objects                  FALSE
_gc_read_mostly_locking             if TRUE, enable read-mostly locking                                FALSE

--节点2:
_gc_policy_time                     how often to make object policy decisions in minutes               10
_gc_read_mostly_flush_check         if TRUE, optimize flushes for read mostly objects                  FALSE
_gc_read_mostly_locking             if TRUE, enable read-mostly locking                                TRUE

发现问题,_gc_policy_time隐藏参数,_gc_read_mostly_locking隐藏参数,2个节点值不一致。
解决方法:根据现在正常运行的节点2的值,重新设置这两个值:

alter system set "_gc_read_mostly_locking"=true scope=spfile sid='*';
alter system set "_gc_policy_time"=10 scope=spfile sid='*';
--正常关闭节点1:
shutdown immediate;
--正常启动节点1:
startup

实际执行过程如下:

SQL> alter system set "_gc_read_mostly_locking"=true scope=spfile sid='*';

System altered.

SQL> alter system set "_gc_policy_time"=10 scope=spfile sid='*';

System altered.

SQL> shutdown immediate;
ORA-01507: database not mounted


ORACLE instance shut down.
SQL> startup
ORACLE instance started.

Total System Global Area 9.4869E+10 bytes
Fixed Size                  2264056 bytes
Variable Size            5.1271E+10 bytes
Database Buffers         4.3487E+10 bytes
Redo Buffers              109174784 bytes
Database mounted.
Database opened.

至此RAC节点1启动成功。

3.总结

猜测故障原因应该是之前有人修改数据库隐含参数,误操作只修改了一个实例导致。
当我们操作RAC环境时,一定要注意sid='*'这一点。