监听器Listener是Oracle Client Process和实例远程建立连接关系的必经之路。借助Listener，Client Process可以实现和一个特定的Server Process建立连接关系，开启Session会话，操作Oracle Instance。
在Oracle体系中，Listener是一个独立的进程。Listener的运行是独立于Oracle实例的。在Windows或者Unix/Linux架构中，监听器都是被实现为一个独立的系统进程Process。监听器在工作中，是侍候在特定的端口Port上，接受Client Process通过Oracle Net协议访问。同时，监听器需要知道所在服务器上的Oracle实例提供的Service Name和对应目录，这个过程，我们称之为“Register”（注册）。
对于注册过程，Oracle监听器提供动静态两种注册方法。不同的注册方法有不同的配置方式和特点，也有各自独特的使用场景。本篇就着重介绍一些动静态注册问题。
1、Listener默认动态监听配置
我们的实验从笔者虚拟机的实际配置开始，选择Oracle版本为11gR2。
SQL> select * from v$version;
BANNER
------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
PL/SQL Release 11.2.0.1.0 - Production
CORE 11.2.0.1.0 Production
使用lsnrctl命令查看监听器状态。
[oracle@bsplinux ~]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 15:49:00
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 17-JUL-2012 19:52:13
Uptime 65 days 19 hr. 56 min. 47 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1521)))
Services Summary...
Service "ora11g" has 1 instance(s).
Instance "ora11g", status READY, has 1 handler(s) for this service...
Service "ora11gXDB" has 1 instance(s).
Instance "ora11g", status READY, has 1 handler(s) for this service...
The command completed successfully
在status命令参数结果输出中，我们可以看到监听器的工作状态。此时，Listener使用Oracle NET参数文件listener.ora，同时监听器注册两个服务项目，名称为ora11g和ora11gXDB。从两个服务的READY状态，可以知道使用动态注册方法。
我们在操作系统层面查看listener.ora文件。
[oracle@bsplinux admin]$ pwd
/u01/app/oracle/network/admin
[oracle@bsplinux admin]$ ls -l
total 40
-rw-r--r-- 1 oracle oinstall 288 May 22 21:21 listener1205229PM2122.bak
-rw-r--r-- 1 oracle oinstall 288 May 22 19:57 listener.ora
drwxr-xr-x 2 oracle oinstall 4096 May 22 15:54 samples
-rw-r--r-- 1 oracle oinstall 187 May 9 2007 shrept.lst
-rw-r--r-- 1 oracle oinstall 310 May 22 21:22 tnsnames.ora
[oracle@bsplinux admin]$ cat listener.ora
# listener.ora Network Configuration File: /u01/app/oracle/network/admin/listener.ora
# Generated by Oracle configuration tools.
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = bsplinux)(PORT =1521))
)
)
ADR_BASE_LISTENER = /u01/app
Oracle Net Service三大配置文件为：listener.ora、sqlnet.ora和tnsnames.ora。其中listener.ora定义了监听器信息。在上面的监听器配置信息中，定义了监听器监听端口1521（默认端口）。注意，文件中没有定义与ora11g实例有关的内容。这个就是使用了动态注册机制。
2、动态监听
所谓动态监听，就是在listener.ora文件中，不需要定义实例Instance具体名称和位置。Oracle实例会在运行之后，由后台进程pmon会周期性的（1-3分钟）到指定端口1521进行状态信息通知。Listener就会自动的进行更新Service情况。
在上一个部分，我们已经看到了存在listener.ora文件情况下的动态注册情况。事实上，如果没有listener.ora文件，我们也是可以实现默认的动态注册监听器的功能。
首先，我们删除listener.ora文件。
[oracle@bsplinux admin]$ mv listener.ora listener_bak.ora
[oracle@bsplinux admin]$ ls -l | grep listener.ora
[oracle@bsplinux admin]$
启动监听器。
[oracle@bsplinux admin]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 15:51:50
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Starting /u01/app/oracle/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Log messages written to /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1521)))
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:51:51
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1521)))
The listener supports no services
The command completed successfully
注意，上面的内容中没有Listener Parameter的内容。监听器在1521端口等待。过一分钟左右，注册内容显示。
--Pmon存在
[oracle@bsplinux admin]$ ps -ef | grep pmon
oracle 10442 10359 0 15:52 pts/0 00:00:00 grep pmon
oracle 24187 1 0 Sep11 ? 00:02:33 ora_pmon_ora11g
[oracle@bsplinux admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 15:52:58
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:51:51
Uptime 0 days 0 hr.1 min. 7 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1521)))
Services Summary...
Service "ora11g" has 1 instance(s).
Instance "ora11g", status READY, has 1 handler(s) for this service...
Service "ora11gXDB" has 1 instance(s).
Instance "ora11g", status READY, has 1 handler(s) for this service...
The command completed successfully
动态注册在实际中是非常有用的。pmon后台进程是Oracle实例生死的重要指标，周期性的pmon注册到Listener中，实际上也是实现了一个功能：实例生存状态汇集。
当我们的实例崩溃，但是监听器存活的时候，监听器不能受到pmon的周期性注册信息。监听器也就可以实现某种类型的failover。
但是，动态注册也不是万能的。其中一个问题就是，动态注册只能进行1521的端口注册。如果我们变化端口，就不能实现动态注册方式了。
我们修改listener.ora文件中的端口信息，如果使用非1521端口，就必须使用listener.ora配置。
[oracle@bsplinux admin]$ ls -l
total 44
-rw-r--r-- 1 oracle oinstall 288 May 22 21:21 listener1205229PM2122.bak
-rw-r--r-- 1 oracle oinstall 288 May 22 19:57 listener_bak.ora
-rw-r--r-- 1 oracle oinstall 288 Sep 21 15:56 listener.ora
drwxr-xr-x 2 oracle oinstall 4096 May 22 15:54 samples
-rw-r--r-- 1 oracle oinstall 187 May 9 2007 shrept.lst
-rw-r--r-- 1 oracle oinstall 310 May 22 21:22 tnsnames.ora
--修改参数端口为1522
[oracle@bsplinux admin]$ cat listener.ora
# listener.ora Network Configuration File: /u01/app/oracle/network/admin/listener.ora
# Generated by Oracle configuration tools.
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = bsplinux)(PORT = 1522))
)
)
ADR_BASE_LISTENER = /u01/app
启动监听器，使用1522端口。
[oracle@bsplinux admin]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 15:58:05
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Starting /u01/app/oracle/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.2.0.1.0 - Production
System parameter file is /u01/app/oracle/network/admin/listener.ora
Log messages written to /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening on:(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1522)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:58:05
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
The listener supports no services
The command completed successfully
等待三分钟或者手工进行注册，都不能让1522端口的监听器注册内容。
--三分钟和手工注册尝试
[oracle@bsplinux admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 16:01:12
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1522)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:58:05
Uptime 0 days 0 hr. 3 min. 6 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
The listener supports no services
The command completed successfully
--手工注册监听器
SQL> conn / as sysdba
Connected.
SQL> alter system register;
System altered.
[oracle@bsplinux admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 16:02:42
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1522)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:58:05
Uptime 0 days 0 hr. 4 min. 37 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
The listener supports no services
The command completed successfully
上面告诉我们，虽然动态注册有很多优势，但是只能使用1521端口。这就会产生很大的限制。从安全角度看，我们通常要避免使用默认端口，防止恶意的端口扫描。
那么，我们很多时候，就要选择静态注册方法。
3、静态注册
静态注册是一种古老的注册手段。简单的说，就是监听器的实例注册信息是直接写在listener.ora文件里的。当监听器启动之后，Oracle会根据配置的listener.ora定义的服务去进行连接匹配。
这个过程中，一个重点在于：Oracle的注册信息是写死在文件里面的。监听器并不能像动态注册那样切实知道Oracle实例的情况，所以静态注册的状态取值通常是UNKNOW。
配置监听器静态注册：
[oracle@bsplinux admin]$ cat listener.ora
# listener.ora Network Configuration File: /u01/app/oracle/network/admin/listener.ora
# Generated by Oracle configuration tools.
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME = ora11g)
(ORACLE_HOME = /u01/app/oracle)
(SID_NAME = ora11g)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = bsplinux)(PORT =1522))
)
)
启动监听器：
[oracle@bsplinux admin]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 16:38:59
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Starting /u01/app/oracle/bin/tnslsnr: please wait...
（篇幅原因，省略……）
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
Services Summary...
Service "ora11g" has 1 instance(s).
Instance "ora11g", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
--连接
SQL> conn scott/tiger@ora11g;
Connected.
静态注册的一个问题，在于监听程序是不知道Oracle实例的真实生存情况。即使实例已经崩溃、关闭，监听器也不能知道这个信息。
--关闭Oracle服务器
[oracle@bsplinux admin]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on Fri Sep 21 16:48:40 2012
Copyright (c) 1982, 2009, Oracle. All rights reserved.
SQL> conn / as sysdba
Connected.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL>
--监听器依然提供实例信息；
[oracle@bsplinux admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 16:50:19
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1522)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 16:38:59
Uptime 0 days 0 hr. 11 min. 20 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
Services Summary...
Service "ora11g" has 1 instance(s).
Instance "ora11g", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
4、静态注册与远程服务器启动
静态注册帮助我们解决了一个问题，就是我们如何在Oracle服务器停机的时候，还能够远程通过Oracle Net连接到Oracle，并启动服务器。
在动态注册时，我们远程连接到监听器时，监听器是不能识别请求连接的名称的。这就造成我们不能远程登录。使用静态注册，恰恰可能帮助我们实现这个需求。
C:\Users\Tomas>tnsping ora11gp
TNS Ping Utility for 32-bit Windows: Version 11.2.0.1.0 - Production on 21-9月-
2012 09:38:25
Copyright (c) 1997, 2010, Oracle. All rights reserved.
已使用的参数文件:
D:\oracle\product\11.2.0\client_1\network\admin\sqlnet.ora
已使用TNSNAMES适配器来解析别名
尝试连接(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 10.1.39.69)(PORT = 1522))) (CONNECT_DATA = (SERVICE_NAME = ora11g)))
OK (0毫秒)
使用sqlplus进行连接。
C:\Users\Tomas>sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on星期五9月21 09:38:39 2012
Copyright (c) 1982, 2010, Oracle. All rights reserved.
SQL> conn sys/oracle@ora11gp as sysdba
已连接到空闲例程。
SQL> startup
ORACLE例程已经启动。
Total System Global Area 422670336 bytes
Fixed Size 1336960 bytes
Variable Size 318769536 bytes
Database Buffers 96468992 bytes
Redo Buffers 6094848 bytes
数据库装载完毕。
数据库已经打开。
SQL>
确定服务器启动。
[oracle@bsplinux ~]$ ps -ef | grep pmon
oracle 11002 1 0 16:55 ? 00:00:00 ora_pmon_ora11g
oracle 11147 10784 0 17:02 pts/1 00:00:00 grep pmon
监听器Listener是Oracle Client Process和实例远程建立连接关系的必经之路。借助Listener，Client Process可以实现和一个特定的Server Process建立连接关系，开启Session会话，操作Oracle Instance。
在Oracle体系中，Listener是一个独立的进程。Listener的运行是独立于Oracle实例的。在Windows或者Unix/Linux架构中，监听器都是被实现为一个独立的系统进程Process。监听器在工作中，是侍候在特定的端口Port上，接受Client Process通过Oracle Net协议访问。同时，监听器需要知道所在服务器上的Oracle实例提供的Service Name和对应目录，这个过程，我们称之为“Register”（注册）。
对于注册过程，Oracle监听器提供动静态两种注册方法。不同的注册方法有不同的配置方式和特点，也有各自独特的使用场景。本篇就着重介绍一些动静态注册问题。
1、Listener默认动态监听配置
我们的实验从笔者虚拟机的实际配置开始，选择Oracle版本为11gR2。
SQL> select * from v$version;
BANNER
------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
PL/SQL Release 11.2.0.1.0 - Production
CORE 11.2.0.1.0 Production
使用lsnrctl命令查看监听器状态。
[oracle@bsplinux ~]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 15:49:00
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 17-JUL-2012 19:52:13
Uptime 65 days 19 hr. 56 min. 47 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1521)))
Services Summary...
Service "ora11g" has 1 instance(s).
Instance "ora11g", status READY, has 1 handler(s) for this service...
Service "ora11gXDB" has 1 instance(s).
Instance "ora11g", status READY, has 1 handler(s) for this service...
The command completed successfully
在status命令参数结果输出中，我们可以看到监听器的工作状态。此时，Listener使用Oracle NET参数文件listener.ora，同时监听器注册两个服务项目，名称为ora11g和ora11gXDB。从两个服务的READY状态，可以知道使用动态注册方法。
我们在操作系统层面查看listener.ora文件。
[oracle@bsplinux admin]$ pwd
/u01/app/oracle/network/admin
[oracle@bsplinux admin]$ ls -l
total 40
-rw-r--r-- 1 oracle oinstall 288 May 22 21:21 listener1205229PM2122.bak
-rw-r--r-- 1 oracle oinstall 288 May 22 19:57 listener.ora
drwxr-xr-x 2 oracle oinstall 4096 May 22 15:54 samples
-rw-r--r-- 1 oracle oinstall 187 May 9 2007 shrept.lst
-rw-r--r-- 1 oracle oinstall 310 May 22 21:22 tnsnames.ora
[oracle@bsplinux admin]$ cat listener.ora
# listener.ora Network Configuration File: /u01/app/oracle/network/admin/listener.ora
# Generated by Oracle configuration tools.
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = bsplinux)(PORT =1521))
)
)
ADR_BASE_LISTENER = /u01/app
Oracle Net Service三大配置文件为：listener.ora、sqlnet.ora和tnsnames.ora。其中listener.ora定义了监听器信息。在上面的监听器配置信息中，定义了监听器监听端口1521（默认端口）。注意，文件中没有定义与ora11g实例有关的内容。这个就是使用了动态注册机制。
2、动态监听
所谓动态监听，就是在listener.ora文件中，不需要定义实例Instance具体名称和位置。Oracle实例会在运行之后，由后台进程pmon会周期性的（1-3分钟）到指定端口1521进行状态信息通知。Listener就会自动的进行更新Service情况。
在上一个部分，我们已经看到了存在listener.ora文件情况下的动态注册情况。事实上，如果没有listener.ora文件，我们也是可以实现默认的动态注册监听器的功能。
首先，我们删除listener.ora文件。
[oracle@bsplinux admin]$ mv listener.ora listener_bak.ora
[oracle@bsplinux admin]$ ls -l | grep listener.ora
[oracle@bsplinux admin]$
启动监听器。
[oracle@bsplinux admin]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 15:51:50
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Starting /u01/app/oracle/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Log messages written to /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1521)))
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:51:51
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1521)))
The listener supports no services
The command completed successfully
注意，上面的内容中没有Listener Parameter的内容。监听器在1521端口等待。过一分钟左右，注册内容显示。
--Pmon存在
[oracle@bsplinux admin]$ ps -ef | grep pmon
oracle 10442 10359 0 15:52 pts/0 00:00:00 grep pmon
oracle 24187 1 0 Sep11 ? 00:02:33 ora_pmon_ora11g
[oracle@bsplinux admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 15:52:58
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:51:51
Uptime 0 days 0 hr.1 min. 7 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1521)))
Services Summary...
Service "ora11g" has 1 instance(s).
Instance "ora11g", status READY, has 1 handler(s) for this service...
Service "ora11gXDB" has 1 instance(s).
Instance "ora11g", status READY, has 1 handler(s) for this service...
The command completed successfully
动态注册在实际中是非常有用的。pmon后台进程是Oracle实例生死的重要指标，周期性的pmon注册到Listener中，实际上也是实现了一个功能：实例生存状态汇集。
当我们的实例崩溃，但是监听器存活的时候，监听器不能受到pmon的周期性注册信息。监听器也就可以实现某种类型的failover。
但是，动态注册也不是万能的。其中一个问题就是，动态注册只能进行1521的端口注册。如果我们变化端口，就不能实现动态注册方式了。
我们修改listener.ora文件中的端口信息，如果使用非1521端口，就必须使用listener.ora配置。
[oracle@bsplinux admin]$ ls -l
total 44
-rw-r--r-- 1 oracle oinstall 288 May 22 21:21 listener1205229PM2122.bak
-rw-r--r-- 1 oracle oinstall 288 May 22 19:57 listener_bak.ora
-rw-r--r-- 1 oracle oinstall 288 Sep 21 15:56 listener.ora
drwxr-xr-x 2 oracle oinstall 4096 May 22 15:54 samples
-rw-r--r-- 1 oracle oinstall 187 May 9 2007 shrept.lst
-rw-r--r-- 1 oracle oinstall 310 May 22 21:22 tnsnames.ora
--修改参数端口为1522
[oracle@bsplinux admin]$ cat listener.ora
# listener.ora Network Configuration File: /u01/app/oracle/network/admin/listener.ora
# Generated by Oracle configuration tools.
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = bsplinux)(PORT = 1522))
)
)
ADR_BASE_LISTENER = /u01/app
启动监听器，使用1522端口。
[oracle@bsplinux admin]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 15:58:05
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Starting /u01/app/oracle/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 11.2.0.1.0 - Production
System parameter file is /u01/app/oracle/network/admin/listener.ora
Log messages written to /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening on:(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1522)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:58:05
Uptime 0 days 0 hr. 0 min. 0 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
The listener supports no services
The command completed successfully
等待三分钟或者手工进行注册，都不能让1522端口的监听器注册内容。
--三分钟和手工注册尝试
[oracle@bsplinux admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 16:01:12
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1522)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:58:05
Uptime 0 days 0 hr. 3 min. 6 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
The listener supports no services
The command completed successfully
--手工注册监听器
SQL> conn / as sysdba
Connected.
SQL> alter system register;
System altered.
[oracle@bsplinux admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 16:02:42
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1522)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 15:58:05
Uptime 0 days 0 hr. 4 min. 37 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
The listener supports no services
The command completed successfully
上面告诉我们，虽然动态注册有很多优势，但是只能使用1521端口。这就会产生很大的限制。从安全角度看，我们通常要避免使用默认端口，防止恶意的端口扫描。
那么，我们很多时候，就要选择静态注册方法。
3、静态注册
静态注册是一种古老的注册手段。简单的说，就是监听器的实例注册信息是直接写在listener.ora文件里的。当监听器启动之后，Oracle会根据配置的listener.ora定义的服务去进行连接匹配。
这个过程中，一个重点在于：Oracle的注册信息是写死在文件里面的。监听器并不能像动态注册那样切实知道Oracle实例的情况，所以静态注册的状态取值通常是UNKNOW。
配置监听器静态注册：
[oracle@bsplinux admin]$ cat listener.ora
# listener.ora Network Configuration File: /u01/app/oracle/network/admin/listener.ora
# Generated by Oracle configuration tools.
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME = ora11g)
(ORACLE_HOME = /u01/app/oracle)
(SID_NAME = ora11g)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = bsplinux)(PORT =1522))
)
)
启动监听器：
[oracle@bsplinux admin]$ lsnrctl start
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 16:38:59
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Starting /u01/app/oracle/bin/tnslsnr: please wait...
（篇幅原因，省略……）
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
Services Summary...
Service "ora11g" has 1 instance(s).
Instance "ora11g", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
--连接
SQL> conn scott/tiger@ora11g;
Connected.
静态注册的一个问题，在于监听程序是不知道Oracle实例的真实生存情况。即使实例已经崩溃、关闭，监听器也不能知道这个信息。
--关闭Oracle服务器
[oracle@bsplinux admin]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on Fri Sep 21 16:48:40 2012
Copyright (c) 1982, 2009, Oracle. All rights reserved.
SQL> conn / as sysdba
Connected.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL>
--监听器依然提供实例信息；
[oracle@bsplinux admin]$ lsnrctl status
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 21-SEP-2012 16:50:19
Copyright (c) 1991, 2009, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=bsplinux)(PORT=1522)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.1.0 - Production
Start Date 21-SEP-2012 16:38:59
Uptime 0 days 0 hr. 11 min. 20 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/app/oracle/network/admin/listener.ora
Listener Log File /u01/app/diag/tnslsnr/bsplinux/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=bsplinux)(PORT=1522)))
Services Summary...
Service "ora11g" has 1 instance(s).
Instance "ora11g", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
4、静态注册与远程服务器启动
静态注册帮助我们解决了一个问题，就是我们如何在Oracle服务器停机的时候，还能够远程通过Oracle Net连接到Oracle，并启动服务器。
在动态注册时，我们远程连接到监听器时，监听器是不能识别请求连接的名称的。这就造成我们不能远程登录。使用静态注册，恰恰可能帮助我们实现这个需求。
C:\Users\Tomas>tnsping ora11gp
TNS Ping Utility for 32-bit Windows: Version 11.2.0.1.0 - Production on 21-9月-
2012 09:38:25
Copyright (c) 1997, 2010, Oracle. All rights reserved.
已使用的参数文件:
D:\oracle\product\11.2.0\client_1\network\admin\sqlnet.ora
已使用TNSNAMES适配器来解析别名
尝试连接(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 10.1.39.69)(PORT = 1522))) (CONNECT_DATA = (SERVICE_NAME = ora11g)))
OK (0毫秒)
使用sqlplus进行连接。
C:\Users\Tomas>sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on星期五9月21 09:38:39 2012
Copyright (c) 1982, 2010, Oracle. All rights reserved.
SQL> conn sys/oracle@ora11gp as sysdba
已连接到空闲例程。
SQL> startup
ORACLE例程已经启动。
Total System Global Area 422670336 bytes
Fixed Size 1336960 bytes
Variable Size 318769536 bytes
Database Buffers 96468992 bytes
Redo Buffers 6094848 bytes
数据库装载完毕。
数据库已经打开。
SQL>
确定服务器启动。
[oracle@bsplinux ~]$ ps -ef | grep pmon
oracle 11002 1 0 16:55 ? 00:00:00 ora_pmon_ora11g
oracle 11147 10784 0 17:02 pts/1 00:00:00 grep pmon
