Oracle 11g数据库启动错误总结
1.启动数据库时提示ORA-00845: MEMORY_TARGET not supported on this system
  (在Oracle 11g中新增的内存自动管理的参数MEMORY_TARGET,它能自动调整SGA和PGA,这个特性需要用到/dev/shm共享文件系统,而且要求/dev/shm必须大于MEMORY_TARGET,如果/dev/shm比MEMORY_TARGET小就会报错)
图:

解决方法:
[root@CentOS ~]# df -h 
Filesystem            Size  Used Avail Use% Mounted on 
/dev/mapper/VolGroup-lv_root      25G   11G   14G  45% / 
tmpfs                 1.0G  751M  274M  74% /dev/shm     --是因为个值小了 
/dev/sda1             485M   30M  430M   7% /boot
/dev/sr0              3.6G  3.6G     0 100% /media/CentOS_6.4_Final 
[root@centos ~]# mount -o remount,size=2G /dev/shm    --修改大小,就不会报错了 
[root@centos ~]# df -h 
Filesystem            Size  Used Avail Use% Mounted on 
/dev/mapper/VolGroup-lv_root
25G   11G   14G  45% / 
tmpfs                 2.0G  751M  1.3G  37% /dev/shm
/dev/sda1             485M   30M  430M   7% /boot
/dev/sr0              3.6G  3.6G     0 100% /media/CentOS_6.4_Final 
[root@centos ~]#
测试:
2.启动oem控制界面出错
[oracle@centos ~]$ emctl stop dbconsole 
Oracle Enterprise Manager 11g Database Control Release 11.2.0.1.0 
Copyright (c) 1996, 2009 Oracle Corporation.  All rights reserved. 
https://centos:1158/em/console/aboutApplication
Stopping Oracle Enterprise Manager 11g Database Control ... 
...  Stopped. 
[oracle@centos ~]$ emctl start dbconsole 
Oracle Enterprise Manager 11g Database Control Release 11.2.0.1.0 
Copyright (c) 1996, 2009 Oracle Corporation.  All rights reserved. 
https://centos:1158/em/console/aboutApplication
Starting Oracle Enterprise Manager 11g Database Control 
.................................................................................... 
......... failed. 
------------------------------------------------------------------ 
Logs are generated in directory /home/oracle/app/oracle/product/11.2.0/dbhome_1/centos_orcl/sysman/log
[oracle@centos ~]$ tailf  -n 3  /home/oracle/app/oracle/product/11.2.0/dbhome_1/centos_orcl/sysman/log/emdctl.trc    --查看最后3行日志,提示路由和主机错误 
2014-01-23 14:54:47,568 Thread-3032057536 WARN  http: nmehl_connect_internal: connect failed to (centos:1158): No route to host (error = 113) 
2014-01-23 15:02:50,071 Thread-3032803008 WARN  http: nmehl_connect_internal: connect failed to (centos:3938): No route to host (error = 113) 
2014-01-23 15:02:50,073 Thread-3032803008 ERROR main: nmectla_agentctl: Error connecting to https://centos:3938/emd/main. Returning status code 1
 解决方法:
[root@centos ~]# ifconfig eth1    --检查服务器的路由和主机IP地址,最好设置为静态的 
eth1      Link encap:Ethernet  HWaddr 08:00:27:5C:4A:F6 
inet addr:2.2.2.114  Bcast:2.2.2.255  Mask:255.255.255.0 
inet6 addr: fe80::a00:27ff:fe5c:4af6/64 Scope:Link 
UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1 
RX packets:88220 errors:0 dropped:0 overruns:0 frame:0 
TX packets:43011 errors:0 dropped:0 overruns:0 carrier:0 
collisions:0 txqueuelen:1000 
RX bytes:6611001 (6.3 MiB)  TX bytes:29439365 (28.0 MiB) 
[root@centos ~]# route  -n 
Kernel IP routing table 
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface 
2.2.2.0         0.0.0.0         255.255.255.0   U     1      0        0 eth1 
0.0.0.0         2.2.2.1         0.0.0.0         UG    0      0        0 eth1 
[root@centos ~]#
测试:
[oracle@centos ~]$ emctl start dbconsole     --启动成功了 
Oracle Enterprise Manager 11g Database Control Release 11.2.0.1.0 
Copyright (c) 1996, 2009 Oracle Corporation.  All rights reserved. 
https://centos:1158/em/console/aboutApplication
Starting Oracle Enterprise Manager 11g Database Control ........ started. 
------------------------------------------------------------------ 
Logs are generated in directory /home/oracle/app/oracle/product/11.2.0/dbhome_1/centos_orcl/sysman/log
[oracle@centos ~]$
3.控制文件丢失(由于控制文件丢失,数据库无法启动)
1234567891011121314 [oracle@centos ~]$ sqlplus 
SQL*Plus: Release 11.2.0.1.0 Production on Sat Jan 25 09:31:04 2014 
Copyright (c) 1982, 2009, Oracle.  All rights reserved. 
Enter user-name: / as sysdba 
Connected to an idle instance. 
SQL> startup 
ORACLE instance started. 
Total System Global Area  661209088 bytes 
Fixed Size          1338560 bytes 
Variable Size         494928704 bytes 
Database Buffers      159383552 bytes 
Redo Buffers            5558272 bytes 
ORA-00205: error in identifying control file, check alert log for more info 
SQL>
解决方法:
[oracle@centos ~]$ ll app/oracle/oradata/orcl/control011.ctl   --查看两个控制文件名 
-rw-r----- 1 oracle oinstall 9748480 Jan 25 09:30 app/oracle/oradata/orcl/control011.ctl 
[oracle@centos ~]$ 
[oracle@centos ~]$ ll app/oracle/flash_recovery_area/orcl/control02.ctl 
-rw-r-----. 1 oracle oinstall 9748480 Jan 25 09:30 app/oracle/flash_recovery_area/orcl/control02.ctl 
[oracle@centos ~]$ vim app/oracle/product/11.2.0/dbhome_1/dbs/initorcl.ora  --打开配置文件看是否控制文件名写对了没有 
*.control_files='/home/oracle/app/oracle/oradata/orcl/control01.ctl','/home/oracle/app/oracle/flash_recovery_area/orcl/control02.ctl'    --第一个控制文件名错了,改对就可以了
测试:
[oracle@centos ~]$ sqlplus 
SQL*Plus: Release 11.2.0.1.0 Production on Sat Jan 25 09:42:31 2014 
Copyright (c) 1982, 2009, Oracle.  All rights reserved. 
Enter user-name: / as sysdba 
Connected to: 
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production 
With the Partitioning, OLAP, Data Mining and Real Application Testing options 
SQL>
