在某些特定的情形下，有时候需要从客户端连接到RAC中指定的实例，而不是由客户端Load_balance来动态选择或者是通过服务器端的监听器根据负载情形来转发。对此我们可以通过为tnsnames.ora中特定的网络服务名添加instance_name子项，或者是单独建立一个指向所需实例的网络服务名，下面描述这两种情形。
一、测试环境
-->Oracle 版本
SQL> select * from v$version where rownumOS 版本
SQL> ho cat /etc/issue
Welcome to SUSE Linux Enterprise Server 10 SP3 (x86_64) - Kernel r (l).
-->RAC 相关信息
SQL> ho /users/oracle/crs_stat.sh
Resource name Target State
-------------- ------ -----
ora.GOBO4.GOBO4A.inst ONLINE ONLINE on bo2dbp
ora.GOBO4.GOBO4B.inst ONLINE ONLINE on bo2dbs
ora.GOBO4.db ONLINE ONLINE on bo2dbp
ora.bo2dbp.ASM1.asm ONLINE ONLINE on bo2dbp
ora.bo2dbp.LISTENER_BO2DBP.lsnr ONLINE ONLINE on bo2dbp
ora.bo2dbp.gsd ONLINE ONLINE on bo2dbp
ora.bo2dbp.ons ONLINE ONLINE on bo2dbp
ora.bo2dbp.vip ONLINE ONLINE on bo2dbp
ora.bo2dbs.ASM2.asm ONLINE ONLINE on bo2dbs
ora.bo2dbs.LISTENER_BO2DBS.lsnr ONLINE ONLINE on bo2dbs
ora.bo2dbs.gsd ONLINE ONLINE on bo2dbs
ora.bo2dbs.ons ONLINE ONLINE on bo2dbs
ora.bo2dbs.vip ONLINE ONLINE on bo2dbs
-->实例GOBO4A上的listener参数
SQL> show parameter instance_name
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
instance_name string GOBO4A
SQL> show parameter listener
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
local_listener string
remote_listener string remote_lsnr_gobo4
-->实例GOBO4B上的listener参数
SQL> show parameter instance_name
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
instance_name string GOBO4B
SQL> show parameter listener
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
local_listener string
remote_listener string remote_lsnr_gobo4
-->服务器端的tnsnames.ora
SQL> ho more $ORACLE_HOME/network/admin/tnsnames.ora
# tnsnames.ora Network Configuration File: /u01/oracle/db/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
remote_lsnr_gobo4 =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.7.61)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.7.62)(PORT = 1521))
)
-->客户端的tnsnames.ora(客户端为suse 10)
oracle@SZDB:~> tail -10 $ORACLE_HOME/network/admin/tnsnames.ora
GOBO4 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.7.61)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.7.62)(PORT = 1521))
(LOAD_BALANCE = yes)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = GOBO4)
)
)
