dbs]$ sqlplus / as sysdba

SQL*Plus: Release 10.2.0.1.0 - Production on Thu Feb 27 14:57:52 2014

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Connected to an idle instance.

SQL> startup
ORA-27125: unable to create shared memory segment
Linux-x86_64 Error: 1: Operation not permitted

这个问题N 年后再遇到，无奈查metalink 解决方案:

# echo 502 > /proc/sys/vm/hugetlb_shm_group
# vi /etc/sysctl.conf

加在最后面
vm.hugetlb_shm_group  = 502

[root@localhost oradisk]# sysctl -p