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

	情景描述：

	在虚拟机上dbca之后，如下，实例是启动的。

	[rose1][oracle][/home/oracle]#ps -ef|grep pmon

	oracle   13637     1  0 05:10 ?        00:00:00 ora_pmon_single

	oracle   13751 12898  0 05:15 pts/3    00:00:00 grep pmon

	于是，直接sqllus / as sysdba.

	SP2-0157: unable to CONNECT to ORACLE after 3 attempts, exiting SQL*Plus

	[rose1][oracle][/home/oracle]#sqlplus "/ as sysdba"

	SQL*Plus: Release 11.2.0.1.0 Production on Wed Dec 28 05:15:26 2016

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

	ERROR:

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

	Enter user-name:

	ERROR:

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

	SP2-0157: unable to CONNECT to ORACLE after 3 attempts, exiting SQL*Plus；

	很奇怪，即便输入了 sysdba/oracle 还是错误。

	仔细想了想才发现，ORACLE_SID忘了指定，于是

	export ORACLE_SID=SINGLE 之后，就没问题了。

ITPub博客

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