一个共享库的问题导致sqlplus用不了了的解决办法!
[root@localhost ~]# su - oracle
[oracle@localhost ~]$ sqlplus / as sysdba
sqlplus: error while loading shared libraries: /oracle/ora11gR2/product/11.2.0/dbhome_1/lib/libclntsh.so.11.1: cannot restore segment prot after reloc: Permission denied
编辑/etc/sysconfig/selinux，找到:
# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
# enforcing - SELinux security policy is enforced.
# permissive - SELinux prints warnings instead of enforcing.
# disabled - SELinux is fully disabled.
SELINUX=enforcing
如果SELINUX已经是 SELINUX=disabled，那么就不用改了，否则就把SELINUX=enforcing 注释掉，新加一行：
SELINUX=disabled
保存，退出。
如果你碰到其他类似提示：
cannot restore segment prot after reloc: Permission denied
哪应该是SELinux的问题，可以考虑把它关闭。
接下来：
[root@localhost ~]# vi /etc/selinux/config
[root@localhost ~]# su - oracle
[oracle@localhost ~]$ sqlpls / as sysdba
-bash: sqlpls: command not found
[oracle@localhost ~]$ sqlplus / as sysdba
sqlplus: error while loading shared libraries: /oracle/ora11gR2/product/11.2.0/dbhome_1/lib/libclntsh.so.11.1: cannot restore segment prot after reloc: Permission denied
[oracle@localhost ~]$ chcon -t texrel_shlib_t /oracle/ora11gR2/product/11.2.0/dbhome_1/lib/libclntsh.so.11.1
[oracle@localhost ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.1.0 Production on Sat Dec 12 16:43:38 2009
Copyright (c) 1982, 2009, Oracle. All rights reserved.
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
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