oracle listener
这一块知识，我相信搞oracle的兄弟都是比较精通的，我也是前段时间公司让做个培训的时候，又把这块又温习了一遍，还是有不少新的收获，今天就搬到这里记录一下
直接传送：使用Oracle Shared Server 时，监听程序将把连接传送给调度程序。专有模式不可用
重定向：listener和服务端不在同一台机器，比如RAC和共享服务
静态注册和动态注册：
1.动态注册：就是PMON主动把信息告诉监听，无需使用listener.ora将文件，lsnrclt status里面read的都是动态。
2.静态注册：监听主动去找服务和实例，需要配置listener.ora文件，指定SID列表，lsnrctl status里面是unknown
先看静态注册，很简单的，保证一看就懂
直接配置listener.ora文件即可
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = oradb)
(ORACLE_HOME = /app/oracle/product/10.2.0/db_1)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST =)(PORT = 1521))
)
)
需要配置SID_NAME LISTENER需要指定相关参数块，这里如果host参数不指定，那么/etc/hosts需要指定，监听启动的时候回去读hosts文件匹配，如果设置为0.0.0.0，那么默认监听所有地址
动态注册以及配置：
1.动态注册不需要配置listener.ora文件，需要配置初始化参数文件，参数service_names,可是设置多个服务名，区分不同业务。
2.如果想配置非默认端口，非默认监听名称，非TCPIP协议，那么需要配置listener.ora 而且需要配置local_listener参数，tnsnames.ora也需要配置。
这里可以看到动态注册分为默认的和非默认的，默认的就是TCP/IP协议，端口是1521，监听名称LISTENER。非默认的大家自己能理解的哦。
默认动态注册实验：
1.Show parameter service_names;
2.Alter system set service_names=zhang,hai,hong;
3. Mv listener.ora listener.ora.bak Lsnrctl stop
4.Lsnrctl start
5.Alter system register;
6.Lsnrctl service;
看结果：
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=172.16.3.174)(PORT=1521)))
Services Summary...
Service "HAI" has 1 instance(s).
Instance "oradb", status READY, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:0 refused:0 state:ready
LOCAL SERVER
Service "HONG" has 1 instance(s).
Instance "oradb", status READY, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:0 refused:0 state:ready
LOCAL SERVER
Service "ZHANG" has 1 instance(s).
Instance "oradb", status READY, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:0 refused:0 state:ready
LOCAL SERVER
Service "oradb" has 2 instance(s).
Instance "oradb", status UNKNOWN, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:0 refused:0
LOCAL SERVER
Instance "oradb", status READY, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:0 refused:0 state:ready
LOCAL SERVER
Service "oradb_XPT" has 1 instance(s).
Instance "oradb", status READY, has 1 handler(s) for this service...
Handler(s):
"DEDICATED" established:0 refused:0 state:ready
LOCAL SERVER
The command completed successfully
相应的client端你如果是用oracle net组件的，那么肯定要配置tnsnames.ora文件
testdb =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 172.168.3.174)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = zhang)
)
)
注意：标红的可以写zhang,hai,hong 或者oradb，就算木有listener.ora 文件，照样可以监听。
下面介绍下非默认动态注册：
这里我们端口用1234,非默认必须需要listener.ora 文件，还有就是local_listener参数.
修改监听文件：
# listener.ora Network Configuration File: /app/oracle/product/10.2.0/db_1/network/admin/listener.ora
# Generated by Oracle configuration tools.
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = oradb)
(ORACLE_HOME = /app/oracle/product/10.2.0/db_1)
)
)
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST =172.16.3.174)(PORT = 1234))
)
)
修改local_listener参数：Alter system set local_listener=‘(ADDRESS = (PROTOCOL = TCP)(HOST =)(PORT = 1234))’;
注意这里，以上修改参数等同于以下配置：
配置服务端的tnsnames.ora文件
hankzhang =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST =)(PORT = 1234))
)
)
然后再设置参数： Alter system set local_listener=hankzhang;
以上两种方法效果是一样滴。
lisnrctl status看一下：
至于RAC的listener配置，呵呵，大同小异，不过还是有区别的，这里先提以下，有时间再继续。
RAC在监听端也可以负载均衡的哦，呵呵，当然这是在RAC双主模式的情况下，而且需要配置REMOTE_LISTENER，配置tnsnames.ora文件，监听暂时先到这里。