数据库版本：
11.2.0.3
问题现象：
今天在启动一台测试数据库的时候，发现db不能open，报错如下：
ERROR at line 1:
ORA-00600: internal error code, arguments: [kcratr_scan_lastbwr], [], [], [],[], [], [], [], [], [], [], []
解决过程：
1、检查alert日志
Mon Jul 22 11:35:12 2013
ALTER DATABASE OPEN
Beginning crash recovery of 1 threads
parallel recovery started with 3 processes
Started redo scan
Hex dump of (file 3, block 272) in trace file /opt/oracle/diag/rdbms/ebai/ebai/trace/ebai_ora_4930.trc
Reading datafile '/oracle/oradata/ebai/undotbs01.dbf' for corruption at rdba: 0x00c00110 (file 3, block 272)
Reread (file 3, block 272) found same corrupt data (logically corrupt)
Write verification failed for File 3 Block 272 (rdba 0xc00110)
Errors in file /opt/oracle/diag/rdbms/ebai/ebai/trace/ebai_ora_4930.trc (incident=71353):
ORA-00600: internal error code, arguments: [kcratr_scan_lastbwr], [], [], [], [], [], [], [], [], [], [], []
Incident details in: /opt/oracle/diag/rdbms/ebai/ebai/incident/incdir_71353/ebai_ora_4930_i71353.trc
Use ADRCI or Support Workbench to package the incident.
See Note 411.1 at My Oracle Support for error and packaging details.
Aborting crash recovery due to error 600
Errors in file /opt/oracle/diag/rdbms/ebai/ebai/trace/ebai_ora_4930.trc:
ORA-00600: internal error code, arguments: [kcratr_scan_lastbwr], [], [], [], [], [], [], [], [], [], [], []
Errors in file /opt/oracle/diag/rdbms/ebai/ebai/trace/ebai_ora_4930.trc:
ORA-00600: internal error code, arguments: [kcratr_scan_lastbwr], [], [], [], [], [], [], [], [], [], [], []
ORA-600 signalled during: ALTER DATABASE OPEN...
Dumping diagnostic data in directory=[cdmp_20130722113516], requested by (instance=1, osid=4930), summary=[incident=71353].
Mon Jul 22 11:36:11 2013
Sweep [inc][71353]: completed
Sweep [inc2][71353]: completed
2、分析并解决问题
alert日志里边其实已经说得很清楚了，实际上连trace文件基本都不需要查看了。上网简单goole了一下，就有解决办法，直接噶搞吧。
suse11sp2:/oracle/oraarch> sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Mon Jul 22 14:45:49 2013
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL> select status from v$instance;
STATUS
------------
MOUNTED
SQL> select open_mode from v$database;
OPEN_MODE
--------------------
MOUNTED
SQL> recover database;
Media recovery complete.
SQL>
SQL>
SQL> alter database open;
Database altered.
SQL>
SQL>
SQL> select status from v$instance;
STATUS
------------
OPEN
SQL> select open_mode from v$database;
OPEN_MODE
--------------------
READ WRITE
3、验证处理效果
执行一次干净关闭，然后在打开，不在报错，问题处理完毕。
SQL> alter system checkpoint;
System altered.
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL>
SQL>
SQL>
SQL>
SQL> startup
ORACLE instance started.
Total System Global Area 4125462528 bytes
Fixed Size 2234840 bytes
Variable Size 956302888 bytes
Database Buffers 3154116608 bytes
Redo Buffers 12808192 bytes
Database mounted.
Database opened.
SQL>
SQL>