最近由于数据库hang住，无奈之下直接干掉了pmon进程，再次启动的时候收到了ORA-01092: Oracle instance terminated. Disconnection forced以及ORA-12432: LBAC error: zllegnp:OCIStmtExecute。这下好了，有的整了，是个从来没有遇见的错误。下面是对这个错误的描述与解决。

1、故障描述
idle> startup
ORACLE instance started.

Total System Global Area  238530560 bytes
Fixed Size                  1335724 bytes
Variable Size            167775828 bytes
Database Buffers          62914560 bytes
Redo Buffers                6504448 bytes
Database mounted.
ORA-01092: ORACLE instance terminated. Disconnection forced
ORA-12432: LBAC error: zllegnp:OCIStmtExecute
Process ID: 10704
Session ID: 125 Serial number: 5

2、故障分析
--首先看看提示的几个ORA说什么
[oracle@linux1 ~]$ oerr ora 1092
01092, 00000, "ORACLE instance terminated. Disconnection forced"
// *Cause:  The instance this process was connected to was terminated
//          abnormally, probably via a shutdown abort. This process
//          was forced to disconnect from the instance.
// *Action: Examine the alert log for more details. When the instance has been
//          restarted, retry action.
--上面的 ora 1092通常由于shutdown abort导致，需要查看alert日志

[oracle@linux1 ~]$ oerr ora 12432
12432, 00000, "LBAC error: %s"
// *Cause:  LBAC enforcement resulted in an error.
// *Action: Correct the problem identified in the error message.
--上面ora 12432是关于LBAC的错误

--下面查看alert日志及其产生的trace文件
$ tail -fn 50 /u02/database/usbo/diag/rdbms/usbo/usbo/trace/alert_usbo.log
Tue Sep 03 14:58:39 2013
ARC3 started with pid=29, OS id=10716
SMON: enabling cache recovery
Archived Log entry 53 added for thread 1 sequence 57 ID 0xcde7041e dest 1:
Successfully onlined Undo Tablespace 2.
Verifying file header compatibility for 11g tablespace encryption..
Verifying 11g file header compatibility for tablespace encryption completed
SMON: enabling tx recovery
Database Characterset is AL32UTF8
No Resource Manager plan active
Errors in file /u02/database/usbo/diag/rdbms/usbo/usbo/trace/usbo_ora_10704.trc:
ORA-12432: LBAC error: zllegnp:OCIStmtExecute
Errors in file /u02/database/usbo/diag/rdbms/usbo/usbo/trace/usbo_ora_10704.trc:
ORA-12432: LBAC error: zllegnp:OCIStmtExecute
Error 12432 happened during db open, shutting down database
USER (ospid: 10704): terminating the instance due to error 12432
Instance terminated by USER, pid = 10704
ORA-1092 signalled during: ALTER DATABASE OPEN...
opiodr aborting process unknown ospid (10704) as a result of ORA-1092
Tue Sep 03 14:58:40 2013
ORA-1092 : opitsk aborting process

$ tail -10 /u02/database/usbo/diag/rdbms/usbo/usbo/trace/usbo_ora_10704.trc
Avg compares per lookup = 173/173 = 1.0
----------------------------------------------
Recovery sets nab of thread 1 seq 57 to 72 with 8 zeroblks

*** 2013-09-03 14:58:39.830
ORA-12432: LBAC error: zllegnp:OCIStmtExecute
ORA-12432: LBAC error: zllegnp:OCIStmtExecute

*** 2013-09-03 14:58:39.830
USER (ospid: 10704): terminating the instance due to error 12432
--上面的这些信息比较笼统，有些不好确认，查询metalink，找到了解决方案
--ORA-01092 ORA-12432 LBAC ERROR ZLLEGNP While Starting Up An Instance (Doc ID 735801.1)
--尽管其版本范围是Oracle Database - Enterprise Edition - Version 11.1.0.6 to 11.1.0.6 [Release 11.1]，我的11.2版本依旧适用
--Oracle给出的无法启动的原因
The issue happens because the OLS metadata is incomplete as a result of a shutdown abort executed while the script catnools.sql (or catols.sql)  was running.

3、故障解决
--Oracle给出的解决方案
--To solve this situation the LBAC option has to be disabled:
Step 1
  cd $ORACLE_HOME/rdbms/lib
  make -f ins_rdbms.mk lbac_off ioracle

-- Author  : Robinson Cheng
-- Blog    : http://www.linuxidc.com
-- DB Forum : http://www.linuxidc.com

Step 2
$ sqlplus "/ as sysdba"
SQL> startup migrate
SQL> @?/rdbms/admin/catnools.sql
SQL> shutdown immediate
SQL> startup
SQL> select * from v$version where rownum