[oracle@up ~]$ sql / as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Sat Feb 11 15:29:31 2017

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

ERROR:

ORA-12162: TNS:net service name is incorrectly specified

报错显示指定的网络名称不正确

查看.bash_profile文件

export PATH

export ORACLE_BASE=/u01/oracle

export ORACLE_HOME=$ORACLE_BASE/product/11.2.0

export ORACLR_SID=ora11g

export PATH=$PATH:$HOME/bin:$ORACLE_HOME/bin

export LD_LIBRARY_PATH=$ORACLE_HOME/lib:/lib:/usr/lib

发现ORACLE_SID变量，名称书写错误，更正变量名称，重新登录

[oracle@up ~]$ sql / as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Sat Feb 11 15:37:02 2017

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> 

登录成功

ORA-12162: TNS:net service name is incorrectly specified