【Oracle】service_name和service_names的关系

从oracle9i开始，后台进程PMON自动在监听器中注册初始化参数SERVICE_NAMES中定义的服务名，SERVICE_NAMES默认为db_name.db_dimain。客户端tns配置中SERVICE_NAME的名称必须是SERVICE_NAMES或其中的一个NAME。

1 listenter.ora文件中的 GLOBAL_DBNAME和tnsnames.ora文件SERVICE_NAME的配置一样时，GLOBAL_DBNAME = A, 连接串中的SERVICE_NAME = A,此时就可以连接上数据库。根据tnsnames.ora文件中的连接串中的SERVICE_NAME = A 找到监听器listener.ora中的SID_DESC = (GLOBAL_DBNAME= A)，之后在找到SID_NAME, 来连接到数据库实例。

2listenter.ora文件中的 GLOBAL_DBNAME和tnsnames.ora文件的SERVICE_NAME的配置一样时，tnsnames.ora中的SERVICE_NAME要与参数文件中的SERVICE_NAMES 参数一样或者是其中之一，否则无法通过tns连接到数据库。

tnsnames.ora文件中的service_name 和 listener.oar文件中的GLOBAL_DBNAME一样的情况：

查看tnsnames.ora文件的配置信息：

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>cat tnsnames.ora 

# tnsnames.ora Network Configuration File: /opt/oracle/11.2.0/alifpre/network/admin/tnsnames.ora

# Generated by Oracle configuration tools.

YANGDB =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb)

    )

  )

YANGDB1 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb1)

    )

  )

YANGDB2 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb2)

    )

  )

YANGDB3 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb3)

    )

  )

RAC =

  (DESCRIPTION =

    (ADDRESS_LIST =

      (ADDRESS = (PROTOCOL = TCP)(HOST = 10.250.7.200)(PORT = 1521))

    )

    (CONNECT_DATA =

      (SERVICE_NAME = rac)

    )

  )

 监听文件中的配置信息：

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>cat listener.ora 

# listener.ora Network Configuration File: /opt/oracle/11.2.0/alifpre/network/admin/listener.ora

# Generated by Oracle configuration tools.

SID_LIST_LISTENER =

      (SID_LIST =

         (SID_DESC =

           (SID_NAME = PLSExtProc)

             (ORACLE_HOME = /opt/oracle/11.2.0/alifpre)

           (PROGRAM = extproc)

         )

        (SID_DESC =

          (GLOBAL_DBNAME = yangdb)

           (ORACLE_HOME = /opt/oracle/11.2.0/alifpre)

          (SID_NAME = yangdb)

         )

     ) 

yangdb =

  (DESCRIPTION_LIST =

    (DESCRIPTION =

      (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    )

  )

ADR_BASE_LISTENER = /opt/oracle

参数service_names是静态的，必须重启机器才能够生效。

oracle@rac3:/home/oracle>sqlplus "/as sysdba"

SYS@yangdb-rac3> alter system set service_names='yangdb,yangdb1,yangdb2,yangdb3' scope=both;

System altered.

SYS@yangdb-rac3> shutdown immediate

Database closed.

Database dismounted.

ORACLE instance shut down.

SYS@yangdb-rac3> startup 

ORACLE instance started.

Database mounted.

Database opened.

SYS@yangdb-rac3> show parameter service_names

NAME                                 TYPE        VALUE

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

service_names                        string      yangdb,yangdb1,yangdb2,yangdb3

进行连接测试：

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>sqlplus yang/yang@yangdb1

SQL*Plus: Release 11.2.0.1.0 Production on Thu Oct 20 11:12:13 2011

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

YANG@yangdb-rac3> show parameter service_ 

NAME                                 TYPE        VALUE

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

service_names                        string      yangdb,yangdb1,yangdb2,yangdb3

YANG@yangdb-rac3> exit

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>sqlplus yang/yang@yangdb2

SQL*Plus: Release 11.2.0.1.0 Production on Thu Oct 20 11:57:26 2011

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

YANG@yangdb-rac3> show parameter service_

NAME                                 TYPE        VALUE

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

service_names                        string      yangdb,yangdb1,yangdb2,yangdb3

YANG@yangdb-rac3> exit

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>sqlplus yang/yang@yangdb3

SQL*Plus: Release 11.2.0.1.0 Production on Thu Oct 20 11:57:38 2011

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to:

YANG@yangdb-rac3> show parameter service_

NAME                                 TYPE        VALUE

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

service_names                        string      yangdb,yangdb1,yangdb2,yangdb3

YANG@yangdb-rac3> exit

查看监听服务状态，可以知道共有6个监听服务名。

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>lsnrctl service

LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 20-OCT-2011 11:59:11

Copyright (c) 1991, 2009, Oracle.  All rights reserved.

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

Services Summary...

Service "PLSExtProc" has 1 instance(s).

  Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...

    Handler(s):

      "DEDICATED" established:0 refused:0

         LOCAL SERVER

Service "yangdb" has 2 instance(s).

  Instance "yangdb", status UNKNOWN, has 1 handler(s) for this service...

    Handler(s):

      "DEDICATED" established:0 refused:0

         LOCAL SERVER

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

    Handler(s):

      "DEDICATED" established:4 refused:0 state:ready

         LOCAL SERVER

Service "yangdb1" has 1 instance(s).

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

    Handler(s):

      "DEDICATED" established:4 refused:0 state:ready

         LOCAL SERVER

Service "yangdb2" has 1 instance(s).

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

    Handler(s):

      "DEDICATED" established:4 refused:0 state:ready

         LOCAL SERVER

Service "yangdb3" has 1 instance(s).

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

    Handler(s):

      "DEDICATED" established:4 refused:0 state:ready

         LOCAL SERVER

Service "yangdbXDB" has 1 instance(s).

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

    Handler(s):

      "D000" established:0 refused:0 current:0 max:1022 state:ready

         DISPATCHER

         (ADDRESS=(PROTOCOL=tcp)(HOST=rac3)(PORT=45357))

The command completed successfully

tnsnames.ora文件中的service_name 和 参数文件中的service_name不一样的情况：

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>vi tnsnames.ora 

# tnsnames.ora Network Configuration File: /opt/oracle/11.2.0/alifpre/network/admin/tnsnames.ora

# Generated by Oracle configuration tools.

lily =   ----连接标识，可以为任意值

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = lily)

    )

  )

YANGDB1 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb1)

    )

  )

YANGDB2 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb2)

    )

  )

YANGDB3 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb3)

    )

  )

"tnsnames.ora" 60L, 1198C 已写入                            

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>vi listener.ora 

# listener.ora Network Configuration File: /opt/oracle/11.2.0/alifpre/network/admin/listener.ora

# Generated by Oracle configuration tools.

SID_LIST_LISTENER =

      (SID_LIST =

         (SID_DESC =

           (SID_NAME = PLSExtProc)

             (ORACLE_HOME = /opt/oracle/11.2.0/alifpre)

           (PROGRAM = extproc)

         )

        (SID_DESC =

          (GLOBAL_DBNAME = lily)

           (ORACLE_HOME = /opt/oracle/11.2.0/alifpre)

          (SID_NAME = yangdb)

         )

     )

yangdb =

  (DESCRIPTION_LIST =

    (DESCRIPTION =

      (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    )

  )

ADR_BASE_LISTENER = /opt/oracle

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>lsnrctl status

LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 20-OCT-2011 10:58:30

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                27-SEP-2011 21:47:16

Uptime                    22 days 13 hr. 11 min. 14 sec

Trace Level               off

Security                  ON: Local OS Authentication

SNMP                      OFF

Listener Parameter File   /opt/oracle/11.2.0/alifpre/network/admin/listener.ora

Listener Log File         /opt/oracle/diag/tnslsnr/rac3/listener/alert/log.xml

Listening Endpoints Summary...

  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=rac3)(PORT=1521)))

Services Summary...

Service "PLSExtProc" has 1 instance(s).

  Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...

Service "yangdb" has 2 instance(s).

  Instance "yangdb", status UNKNOWN, has 1 handler(s) for this service...

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

Service "yangdb1" has 1 instance(s).

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

Service "yangdb2" has 1 instance(s).

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

Service "yangdb3" has 1 instance(s).

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

Service "yangdbXDB" has 1 instance(s).

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

The command completed successfully

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>lsnrctl service

LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 20-OCT-2011 10:58:37

Copyright (c) 1991, 2009, Oracle.  All rights reserved.

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

Services Summary...

Service "PLSExtProc" has 1 instance(s).

  Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...

    Handler(s):

      "DEDICATED" established:0 refused:0

         LOCAL SERVER

Service "yangdb" has 2 instance(s).

  Instance "yangdb", status UNKNOWN, has 1 handler(s) for this service...

    Handler(s):

      "DEDICATED" established:0 refused:0

         LOCAL SERVER

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

    Handler(s):

      "DEDICATED" established:4 refused:0 state:ready

         LOCAL SERVER

Service "yangdb1" has 1 instance(s).

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

    Handler(s):

      "DEDICATED" established:4 refused:0 state:ready

         LOCAL SERVER

Service "yangdb2" has 1 instance(s).

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

    Handler(s):

      "DEDICATED" established:4 refused:0 state:ready

         LOCAL SERVER

Service "yangdb3" has 1 instance(s).

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

    Handler(s):

      "DEDICATED" established:4 refused:0 state:ready

         LOCAL SERVER

Service "yangdbXDB" has 1 instance(s).

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

    Handler(s):

      "D000" established:0 refused:0 current:0 max:1022 state:ready

         DISPATCHER

         (ADDRESS=(PROTOCOL=tcp)(HOST=rac3)(PORT=45357))

The command completed successfully

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>lsnrctl reload

LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 20-OCT-2011 10:58:45

Copyright (c) 1991, 2009, Oracle.  All rights reserved.

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

The command completed successfully

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>

更改tnsnames.ora文件中的service_name的值 yangdb为lily，并相应的修改listener.ora文件中的global_dbname的值为lily ，也可以成功连接数据库。

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>vi tnsnames.ora 

# tnsnames.ora Network Configuration File: /opt/oracle/11.2.0/alifpre/network/admin/tnsnames.ora

# Generated by Oracle configuration tools.

lily =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = lily)

    )

  )

YANGDB1 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb1)

    )

  )

YANGDB2 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb2)

    )

  )

YANGDB3 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = yangdb3)

    )

  )

"tnsnames.ora" 60L, 1196C 已写入

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>sqlplus yang/yang@lily 

SQL*Plus: Release 11.2.0.1.0 Production on Thu Oct 20 11:00:11 2011

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

YANG@yangdb-rac3> show parameter service_        

NAME                                 TYPE        VALUE

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

service_names                        string      yangdb,yangdb1,yangdb2,yangdb3  --动态监听里面没有lily 这样的服务

YANG@yangdb-rac3> exit

说明：如果 参数文件中的service_names没有lily这个值，但是listener.ora文件中有与之对应的GLOBAL_DBNAME，并且已经启动了静态监听服务，则sqlplus通过@lily也可以连接数据库。

如果没有启动静态监听，即没有lily 这样的service,则不可以连接数据库，(当然修改过之后没有执行reload 或没有重启监听，则还可以连接，因为之前存在，这样的例子不讨论)

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>vi listener.ora     

# listener.ora Network Configuration File: /opt/oracle/11.2.0/alifpre/network/admin/listener.ora

# Generated by Oracle configuration tools.

# SID_LIST_LISTENER =

#      (SID_LIST =

#         (SID_DESC =

#           (SID_NAME = PLSExtProc)

#             (ORACLE_HOME = /opt/oracle/11.2.0/alifpre)

#           (PROGRAM = extproc)

#         )

#        (SID_DESC =

#          (GLOBAL_DBNAME = lily)

#           (ORACLE_HOME = /opt/oracle/11.2.0/alifpre)

#          (SID_NAME = yangdb)

#         )

#     ) 

yangdb =

  (DESCRIPTION_LIST =

    (DESCRIPTION =

      (ADDRESS = (PROTOCOL = TCP)(HOST = rac3)(PORT = 1521))

    )

  )

ADR_BASE_LISTENER = /opt/oracle    

编辑过之后重新启动数据库（可选），重启监听，目的重新注册服务，去掉静态监听的服务。

 SYS@yangdb-rac3> shutdown immediate

Database closed.

Database dismounted.

ORACLE instance shut down.

SYS@yangdb-rac3>  startup 

Database mounted.

Database opened. 

SYS@yangdb-rac3> 

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>lsnrctl start

LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 20-OCT-2011 11:11:24

Copyright (c) 1991, 2009, Oracle.  All rights reserved.

Starting /opt/oracle/11.2.0/alifpre/bin/tnslsnr: please wait...

TNSLSNR for Linux: Version 11.2.0.1.0 - Production

System parameter file is /opt/oracle/11.2.0/alifpre/network/admin/listener.ora

Log messages written to /opt/oracle/diag/tnslsnr/rac3/listener/alert/log.xml

Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=rac3)(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                20-OCT-2011 11:11:24

Uptime                    0 days 0 hr. 0 min. 0 sec

Trace Level               off

Security                  ON: Local OS Authentication

SNMP                      OFF

Listener Parameter File   /opt/oracle/11.2.0/alifpre/network/admin/listener.ora

Listener Log File         /opt/oracle/diag/tnslsnr/rac3/listener/alert/log.xml

Listening Endpoints Summary...

  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=rac3)(PORT=1521)))

The listener supports no services  --没有静态监听服务，这时只能通过动态监听的服务来连接到数据库。

The command completed successfully

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>sqlplus yang/yang@lily

SQL*Plus: Release 11.2.0.1.0 Production on Thu Oct 20 11:11:35 2011

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

ERROR:

ORA-12514: TNS:listener does not currently know of service requested in connect 

descriptor --报错，监听没有lily这样的服务

Enter user-name: ^[[ 

--通过pmon动态监听的服务名来连接数据库。

oracle@rac3:/opt/oracle/11.2.0/alifpre/network/admin>sqlplus yang/yang@yangdb1

SQL*Plus: Release 11.2.0.1.0 Production on Thu Oct 20 11:12:13 2011

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

YANG@yangdb-rac3> show parameter service_ 

NAME                                 TYPE        VALUE

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

service_names                        string      yangdb,yangdb1,yangdb2,yangdb3

时间： 2024-09-29 07:21:50

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