【監聽】tnsname.ora檔案理解

tnsnames.ora檔案說明，類似host檔案，客戶端不需要知道資料庫名和例項名，只需要知道該資料庫對外提供的服務名（RAC環境下服務名下面還可以增加一個INSTANCE_NAME子配置選項）或SID就可以申請連線到資料庫

 

TNSNAMES.ORA中配置service_name和配置sid都可以，但是sqlplus必須使用service_name

 

 

TNSNAMES.ORA中SERVICE_NAME、SID的區別

SID只指定一個例項，而SERVICE_NAME在RAC環境中指定多個例項。

如果配置RAC的某一臺機器就配置SID，如果配置負載均衡則配置service_name，當然在service_name下面在指定instance_name也可以指定單獨的例項

 

LUXUS =

  (DESCRIPTION =

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

    (CONNECT_DATA =

      (SERVER = DEDICATED)//表示採用專用模式，如果服務端不是專用模式，則採用服務端的預設連線方式, 服務端配置為共享伺服器的情況，Client可以用共享伺服器或者專用伺服器來聯接資料庫，這個引數的控制就是SERVER

      (SERVICE_NAME = luxus)

    )

  )

 

 

LUXUS2 =

  (DESCRIPTION =

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

(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1523))/*配置了一個負載均衡，連線luxus2時會自動連線到一個埠1521或1523的服務*/

(CONNECT_DATA =

      (SERVICE_NAME = luxus)

    )

  )

 

 

 

RAC的配置，標準配置如下

testdb =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = 10.98.0.142)(PORT = 1521))

    (ADDRESS = (PROTOCOL = TCP)(HOST = 10.98.0.143)(PORT = 1521))

    (LOAD_BALANCE = yes)

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = TESTDB)

       (FAILOVER_MODE=

         (TYPE = session)

         (METHOD = basic)

         (RETRIES = 180)

         (DELAY = 5)

    )

    )

  )

 

 

RAC的配置，也可以採用直接使用SID來指明單獨例項

testdb1 =

  (DESCRIPTION =

    (ADDRESS_LIST =

      (ADDRESS = (PROTOCOL = TCP)(HOST = 10.98.0.142)(PORT = 1521))

    )

    (CONNECT_DATA =

      (SID = TESTDB1)

    )

  )

 

testdb2 =

  (DESCRIPTION =

    (ADDRESS_LIST =

      (ADDRESS = (PROTOCOL = TCP)(HOST = 10.98.0.143)(PORT = 1521))

    )

    (CONNECT_DATA =

      (SID = TESTDB2)

    )

  )

 

RAC的配置，也可以採用service_name和instance_name來指明單獨例項

testdb1 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = 10.98.0.142)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = TESTDB)

     (INSTANCE_NAME=TESTDB1)

    )

  )

 

testdb2 =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = 10.98.0.143)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME =TESTDB)

      (INSTANCE_NAME=TESTDB2)

    )

  )