ORACLE動態監聽總結

本文件介紹ORACLE動態監聽服務的配置及原理；

$ORACLE_HOME/network/admin/listener.ora

ORACLE例項在啟動時，或使用命令ALTER SYSTEM REGISTER ，或每隔一分鐘，PMON程式會向監聽進行動態註冊1、監聽在啟動時，會從$ORACLE_HOME/network/admin/listener.ora讀取監聽配置，如果該檔案不存在，則監聽會在主機名對應的IP和1521埠上進行監聽。可以看到監聽剛剛啟動的時候，並沒有註冊的服務
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、過了大概1分鐘，PMON程式會將服務註冊進來
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程式只向預設的1521埠的監聽註冊，當監聽不在1521埠時，需要使用下面的方法：

a、直接在引數local_listener中輸入監聽地址，PMON程式會根據此資訊，並進行註冊
sys@TEST>alter system set local_listener='(address=(protocol=tcp)(port=1521)(host= 192.168.19.128))' scope=both;

System altered.

b、或者只在引數local_listener中輸入監聽的名稱
sys@TEST>alter system set local_listener='test';

System altered.

在$ORACLE_HOME/network/admin/tnsnames.ora中包含監聽地址，PMON程式會從此處得監聽資訊，並進行註冊
TEST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.102)(PORT = 1522))

4、但有3點需要注意的地方：
a、PMON程式1分鐘執行一次，當監聽剛剛啟動的時候，可能服務還沒有註冊進去，這時候是不能使用此服務的
b、在修改local_listener引數時，PMON程式也會重新註冊一次
c、如果資料庫shutdown後，PMON程式也停止了，服務會從監聽中刪除，這時候只能使用OS認證的方式連入資料庫

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

sys@TEST>shutdown 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

監聽服務是根據listener.ora設定的埠進行監聽的，資料庫啟動的時候會預設根據1521的埠進行註冊；

如果預設的埠不是1521的話，就需要修改引數檔案的資訊；