1 动态监听

本文档介绍ORACLE动态监听服务的配置及原理；

1.1 监听文件

$ORACLE_HOME/network/admin/listener.ora

1.2 动态监听

ORACLE实例在启动时，或使用命令ALTER SYSTEM REGISTER ，或每隔一分钟，PMON进程会向监听进行动态注册1、监听在启动时，会从$ORACLE_HOME/network/admin/listener.ora读取监听配置，如果该文件不存在，则监听会在主机名对应的IP和1521端口上进行监听。可以看到监听刚刚启动的时候，并没有注册的服务

LSNRCTL> start

Starting tnslsnr: please wait...

TNSLSNR for 32-bit Windows: Version 10.2.0.1.0 - Production

Log messages written to f:\oracle\product\10.2.0\network\log\listener.log

Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=linan)(PORT=1521)))

Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))

STATUS of the LISTENER

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

Alias LISTENER

Version TNSLSNR for 32-bit Windows: Version 10.2.0.1.0 - Production

Start Date 14-APR-2008 21:29:40

Uptime 0 days 0 hr. 0 min. 2 sec

Trace Level off

Security ON: Local OS Authentication

SNMP OFF

Listener Log File f:\oracle\product\10.2.0\network\log\listener.log

Listening Endpoints Summary...

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=linan)(PORT=1521)))

The listener supports no services

The command completed successfully

2、过了大概1分钟，PMON进程会将服务注册进来

LSNRCTL> status

Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))

STATUS of the LISTENER

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

Alias LISTENER

Version TNSLSNR for 32-bit Windows: Version 10.2.0.1.0 - Production

Start Date 14-APR-2008 21:29:40

Uptime 0 days 0 hr. 1 min. 57 sec

Trace Level off

Security ON: Local OS Authentication

SNMP OFF

Listener Log File f:\oracle\product\10.2.0\network\log\listener.log

Listening Endpoints Summary...

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=linan)(PORT=1521)))

Services Summary...

Service "test" has 1 instance(s).

Instance "test", status READY, has 1 handler(s) for this service...

Service "testXDB" has 1 instance(s).

Instance "test", status READY, has 1 handler(s) for this service...

Service "test_XPT" has 1 instance(s).

Instance "test", status READY, has 1 handler(s) for this service...

The command completed successfully

3、但是PMON进程只向默认的1521端口的监听注册，当监听不在1521端口时，需要使用下面的方法：

a、直接在参数local_listener中输入监听地址，PMON进程会根据此信息，并进行注册

system set local_listener='(address=(protocol=tcp)(port=1527)(host= ekpdbtest))' scope=both;

System altered.

b、或者只在参数local_listener中输入监听的名称

system set local_listener='test';

System altered.

在$ORACLE_HOME/network/admin/tnsnames.ora中包含监听地址，PMON进程会从此处得监听信息，并进行注册

TEST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.102)(PORT = 1522))

4、但有3点需要注意的地方：

a、PMON进程1分钟运行一次，当监听刚刚启动的时候，可能服务还没有注册进去，这时候是不能使用此服务的

b、在修改local_listener参数时，PMON进程也会重新注册一次

c、如果数据库shutdown后，PMON进程也停止了，服务会从监听中删除，这时候只能使用OS认证的方式连入数据库

LSNRCTL> status

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=linan)(PORT=1522)))

STATUS of the LISTENER

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

Alias listener1

Version TNSLSNR for 32-bit Windows: Version 10.2.0.1.0 - Production

Start Date 14-APR-2008 21:14:04

Uptime 0 days 0 hr. 10 min. 15 sec

Trace Level off

Security ON: Local OS Authentication

SNMP OFF

Listener Parameter File f:\oracle\product\10.2.0\network\admin\listener.ora

Listener Log File f:\oracle\product\10.2.0\network\log\listener1.log

Listening Endpoints Summary...

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=linan)(PORT=1522)))

Services Summary...

Service "test" has 1 instance(s).

Instance "test", status BLOCKED, has 1 handler(s) for this service...

Service "testXDB" has 1 instance(s).

Instance "test", status BLOCKED, has 1 handler(s) for this service...

Service "test_XPT" has 1 instance(s).

Instance "test", status BLOCKED, has 1 handler(s) for this service...

The command completed successfully

immediate

Database closed.

Database dismounted.

ORACLE instance shut down.

LSNRCTL> status

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=joeone-1)(PORT=1522)))

STATUS of the LISTENER

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

Alias listener1

Version TNSLSNR for 32-bit Windows: Version 10.2.0.1.0 - Production

Start Date 14-APR-2008 21:14:04

Uptime 0 days 0 hr. 10 min. 49 sec

Trace Level off

Security ON: Local OS Authentication

SNMP OFF

Listener Parameter File f:\oracle\product\10.2.0\network\admin\listener.ora

Listener Log File f:\oracle\product\10.2.0\network\log\listener1.log

Listening Endpoints Summary...

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=linan)(PORT=1522)))

The listener supports no services

The command completed successfully

1.3 动态监听总结

监听服务是根据listener.ora设定的端口进行监听的，数据库启动的时候会默认根据1521的端口进行注册；

如果默认的端口不是1521的话，就需要修改参数文件的信息；