问题报错过程
srv-bioradb:~> sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Thu Jul 25 18:27:45 2013
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup
ORA-00845: MEMORY_TARGET not supported on this system
SQL> show sga;
ORA-01034: ORACLE not available
Process ID: 0
Session ID: 0 Serial number: 0
上网google发现是shm设置太小的问题
重新设置shm
1）卸载shm，遭遇报错
srv-bioradb:~> df -h
df: `/root/.gvfs': Permission denied
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/system-lv_root 358G 8.5G 331G 3% /
devtmpfs 127G 624K 127G 1% /dev
tmpfs 195G 932K 195G 1% /dev/shm
/dev/cciss/c0d0p1 1.6G 106M 1.4G 8% /boot
/dev/mapper/data-lv_data 2.3T 1.8T 364G 84% /oracle
/dev/mapper/oraclevg-oraclelv01 2.9T 201M 2.7T 1% /oracle1
srv-bioradb:~> more /etc/fstab
/dev/system/lv_swap swap swap defaults 0 0
/dev/system/lv_root / ext3 acl,user_xattr 1 1
/dev/disk/by-id/cciss-3600508b1001c59983f902a5494c7d076-part1 /boot
ext3 acl,user_xattr 1 2
#/dev/data/lv_data /oracle_bk ext3 acl,user_xattr 1 2
/dev/data/lv_data /oracle ext3 defaults 0 0
proc /proc proc defaults 0 0
sysfs /sys sysfs noauto 0 0
debugfs /sys/kernel/debug debugfs noauto 0 0
usbfs /proc/bus/usb usbfs noauto 0 0
devpts /dev/pts devpts mode=0620,gid=5 0 0
#/dev/mapper/oraclevg-oraclelv01 /oracle ext3 defaults 0 0
#/dev/mapper/oraclevg-oraclelv02 /oracle/oradata2 ext3 defaults 0 0
srv-bioradb:~>
srv-bioradb:~>
srv-bioradb:~> umount /dev/shm
umount: /dev/shm is not in the fstab (and you are not root)
srv-bioradb:~> exit
exit
srv-bioradb:~ #
srv-bioradb:~ # umount /dev/shm
umount: /dev/shm: device is busy.
(In some cases useful info about processes that use
the device is found by lsof(8) or fuser(1))
srv-bioradb:~ #
2）查看谁在使用shm，踢掉
srv-bioradb:~ # fuser -cu /dev/shm
/dev/shm: 12555m(root) 12614m(root) 12622m(root)
srv-bioradb:~ # ps -ef | grep 12555
root 12555 1 0 Jul24 ? 00:00:05 /usr/lib/gnome-settings-daemon/gnome-settings-daemon
root 43817 43683 0 18:36 pts/2 00:00:00 grep 12555
srv-bioradb:~ # ps -ef | grep 12614
root 12614 12445 0 Jul24 ? 00:00:00 gnome-volume-control-applet
root 43819 43683 0 18:37 pts/2 00:00:00 grep 12614
srv-bioradb:~ # ps -ef | grep 12622
root 12622 1 0 Jul24 ? 00:00:00 /usr/bin/pulseaudio --start
root 43821 43683 0 18:37 pts/2 00:00:00 grep 12622
srv-bioradb:~ # kill -9 12555
srv-bioradb:~ # kill -9 12614
srv-bioradb:~ # kill -9 12622
这里啰嗦一下，查找到的进程必须ps一下看看具体是什么进程在占用shm文件系统，如果是应用程序占用，退出程序。如果是僵死进程或不重要的shell终端，直接kill即可
3）再次卸载shm
srv-bioradb:~ #
srv-bioradb:~ # umount /dev/shm
srv-bioradb:~ #
srv-bioradb:~ # df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/system-lv_root 358G 8.5G 331G 3% /
devtmpfs 127G 624K 127G 1% /dev
/dev/cciss/c0d0p1 1.6G 106M 1.4G 8% /boot
/dev/mapper/data-lv_data 2.3T 1.8T 364G 84% /oracle
/dev/mapper/oraclevg-oraclelv01 2.9T 201M 2.7T 1% /oracle1
srv-bioradb:~ #
4）重新设置shm大小
srv-bioradb:~ # vi /etc/fstab
SQL> host more /etc/fstab
/dev/system/lv_swap swap swap defaults 0 0
/dev/system/lv_root / ext3 acl,user_xattr 1 1
/dev/disk/by-id/cciss-3600508b1001c59983f902a5494c7d076-part1 /boot
ext3 acl,user_xattr 1 2
#/dev/data/lv_data /oracle_bk ext3 acl,user_xattr 1 2
/dev/data/lv_data /oracle ext3 defaults 0 0
proc /proc proc defaults 0 0
sysfs /sys sysfs noauto 0 0
debugfs /sys/kernel/debug debugfs noauto 0 0
usbfs /proc/bus/usb usbfs noauto 0 0
devpts /dev/pts devpts mode=0620,gid=5 0 0
tmpfs /dev/shm tmpfs defaults,size=256G 0 0
#/dev/mapper/oraclevg-oraclelv01 /oracle ext3 defaults 0 0
#/dev/mapper/oraclevg-oraclelv02 /oracle/oradata2 ext3 defaults 0 0
srv-bioradb:~ # mount /dev/shm
srv-bioradb:~ # df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/system-lv_root 358G 8.5G 331G 3% /
devtmpfs 127G 624K 127G 1% /dev
/dev/cciss/c0d0p1 1.6G 106M 1.4G 8% /boot
/dev/mapper/data-lv_data 2.3T 1.8T 364G 84% /oracle
/dev/mapper/oraclevg-oraclelv01 2.9T 201M 2.7T 1% /oracle1
tmpfs 256G 0 256G 0% /dev/shm
srv-bioradb:~ #
srv-bioradb:~ #
srv-bioradb:~ #
启动oracle，不再报错，问题解决
srv-bioradb:~ # whoami
root
srv-bioradb:~ # su - oracle
srv-bioradb:~> sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Thu Jul 25 18:46:06 2013
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup
ORACLE instance started.
Total System Global Area 2.1913E+11 bytes
Fixed Size 2241384 bytes
Variable Size 1.0469E+11 bytes
Database Buffers 1.1435E+11 bytes
Redo Buffers 88821760 bytes
Database mounted.
Database opened.
SQL>
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