客户端连接数据库报错
问题描述:客户端连接数据库报错



ORA-12516: TNS:
监听程序无法找到匹配协议栈的可用句柄

解决过程:

1
。查看当前会话数、
processes

sessions
值,发现
session
数和
2
个参数的
值已经非常逼近



SQL*Plus: Release 10.2.0.1.0 - Production on
星期一
10

9
15:50:21 2006
Copyright (c) 1982, 2005, Oracle. All rights reserved.
SQL> conn / as sysdba
已连接。

SQL> select count(*) from v

session;
COUNT(*)
----------
45







SQL> show parameter processes
NAME TYPE VALUE
------------------------------------ -----------
----------------------
aq_tm_processes integer 0
db_writer_processes integer 1
gcs_server_processes integer 0
job_queue_processes integer 10
log_archive_max_processes integer 2
processes integer 50
SQL> show parameter sessions
NAME TYPE VALUE
------------------------------------ -----------
----------------------
java_max_sessionspace_size integer 0
java_soft_sessionspace_limit integer 0







license_max_sessions integer 0
license_sessions_warning integer 0
logmnr_max_persistent_sessions integer 1
sessions integer 60
shared_server_sessions integer

2
。修改
processes

sessions




SQL> alter system set processes=300 scope=spfile;
系统已更改。

SQL> alter system set sessions=300 scope=spfile;
系统已更改。


3
。查看
processes

sessions
参数,但更改并未生效



SQL> show parameter processes
NAME TYPE VALUE
------------------------------------ -----------
----------------------
aq_tm_processes integer 0
db_writer_processes integer 1
gcs_server_processes integer 0
job_queue_processes integer 10
log_archive_max_processes integer 2
processes integer 50
SQL> show parameter sessions
NAME TYPE VALUE
------------------------------------ -----------
----------------------
java_max_sessionspace_size integer 0
java_soft_sessionspace_limit integer 0
license_max_sessions integer 0
license_sessions_warning integer 0
logmnr_max_persistent_sessions integer 1
sessions integer 60
shared_server_sessions integer

4
。重启数据库,使更改生效






SQL> shutdown immediate


SQL> startup


SQL> show parameter processes
NAME TYPE VALUE
------------------------------------ -----------
----------------------
aq_tm_processes integer 0
db_writer_processes integer 1
gcs_server_processes integer 0
job_queue_processes integer 10
log_archive_max_processes integer 2
processes integer 300
SQL> show parameter sessions
NAME TYPE VALUE
------------------------------------ -----------
----------------------
java_max_sessionspace_size integer 0
java_soft_sessionspace_limit integer 0
license_max_sessions integer 0
license_sessions_warning integer 0
logmnr_max_persistent_sessions integer 1
sessions integer 335
shared_server_sessions integer
最后测试加大连接数到
50

100
都没报
ORA-12516
错误。