当前位置：首页 -> 基础 -> 数据库编程

listener之一二(一)

2014-11-24 12:39:10 · 作者: · 浏览: 2
标签: listener 之一二
listener之一二
一、注册
注册就是将 数据库作为一个服务注册到监听程序。客户端不需要知道数据库名和实例名，只需要
知道该数据库对外提供的服务名就可以申请连接到数据库。这个服务名可以与实例名一致，也可以不
一致，且可以注册多个服务。
注册可以分为静态注册与动态注册，下面分别介绍静态注册和动态注册。
二、静态注册
静态注册就是预先配置好listener.ora文件，配置信息如下： 
#listener.ora
SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = PLSExtProc)
      (ORACLE_HOME = /u01/app/oracle/product/10.2/db_1)
      (PROGRAM = extproc)
    )
    (SID_DESC =
      (SID_NAME = orcl)##数据库的实例名
      (ORACLE_HOME = /u01/app/oracle/product/10.2/db_1)##监听程序所在路径
      (GLOBAL_DBNAME = test01)##数据库对外提供的服务名
    )
  )
LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = db01)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
    )
  )

当用户通过客户端申请连接数据库时，首先通过监听程序读取listener.ora中的配置信息(无论数据库
是否启动，用户的连接请求都会通过监听程序的检查，因为静态监听是无法识别数据库的启动状态的
，只有用户试图连接数据库时，数据库才会返回相关信息。)
下面我们来看下数据库处于打开和关闭状态时，服务test01的实例状态：
1、打开状态 
[oracle@db01 admin]$ lsnrctl status
LSNRCTL for Linux: Version 10.2.0.1.0 - Production on 16-OCT-2013 06:58:27
Copyright (c) 1991, 2005, Oracle.  All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=db01)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for 






Linux: Version 10.2.0.1.0 - Production
Start Date                16-OCT-2013 06:39:09
Uptime                    0 days 0 hr. 19 min. 18 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Parameter File   /u01/app/oracle/product/10.2/db_1/network/admin/listener.ora
Listener Log File         /u01/app/oracle/product/10.2/db_1/network/log/listener.log
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=db01)(PORT=1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC0)))
Services Summary...
Service "PLSExtProc" has 1 instance(s).
  Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "orcl" has 1 instance(s).
  Instance "orcl", status READY, has 1 handler(s) for this service...
Service "orclXDB" has 1 instance(s).
  Instance "orcl", status READY, has 1 handler(s) for this service...
Service "orcl_XPT" has 1 instance(s).
  Instance "orcl", status READY, has 1 handler(s) for this service...
Service "test01" has 1 instance(s).
  Instance "orcl", status UNKNOWN, has 1 handler(s) for this service...   
=>实例orcl的状态为unknown
The command completed successfully
此时当用户通过客户端连接数据库时：
SQL> conn system/hat@test01

已连接。
2、关闭状态： 
[oracle@db01 admin]$ lsnrctl status
LSNRCTL for Linux: Version 10.2.0.1.0 - Production on 16-OCT-2013 06:54:44
Copyright (c) 1991, 2005, Oracle.  All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=db01)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 10.2.0.1.0 - Production
Start Date                16-OCT-2013 06:39:09
Uptime                    0 days 0 hr. 15 min. 35 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Parameter File   /u01/app/oracle/product/10.2/db_1/network/admin/listener.ora
Listener Log File         /u01/app/oracle/product/10.2/db_1/network/log/listener.log
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=db01)(PORT=1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC0)))
Services Summary...