Ora12516:TNS:监听程序找不到符合协议堆栈要求的可用处理程序

解决办法：

processes达到上限，增加processes初始化参数值

SQL> select count(*) from v$process;

COUNT(*)

----------

99

SQL> show parameter process;

NAME TYPE VALUE

------------------------------------ ---------------------- ------------------------------

processes integer 100

SQL> alter system set processes=300 scope=spfile;

System altered.

SQL> shutdown immediate;

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL> startup

ORACLE instance started

select * from v$session;查看连接会话数，必要时可kill掉session