1,  tnsnames.ora on two nodes:
RACTEST =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = racscan.test.com)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = RACTEST.test.com)
    )
  )






RAC1_LOCAL = 
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = rac1vip.test.com)(PORT = 1529))
  )




RAC2_LOCAL = 
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = rac2vip.test.com)(PORT = 1529))
  )




RAC_REMOTE =
          (DESCRIPTION= 
            (ADDRESS_LIST=
                (ADDRESS=(PROTOCOL=tcp)(HOST=rac1vip.test.com)(PORT=1529))
                (ADDRESS=(PROTOCOL=tcp)(HOST=rac2vip.test.com)(PORT=1529))
            )
          )






RAC_BALANCE=
        (DESCRIPTION= 
            (ADDRESS_LIST=
                (LOAD_BALANCE=YES)
                (FAILOVER=YES)
                (ADDRESS=(PROTOCOL=tcp)(HOST=rac1vip.test.com)(PORT=1529))
                (ADDRESS=(PROTOCOL=tcp)(HOST=rac2vip.test.com)(PORT=1529))
            )
            (CONNECT_DATA=
                (SERVICE_NAME=RACTEST.test.com)
            )
        )




2,listener.ora on two nodes:
node1:RAC= 
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = rac1vip.test.com)(PORT = 1529))
)




SID_LIST_RAC=
(SID_LIST=
(SID_DESC = (ORACLE_HOME =/dbfs/app/oracle/product/11.2.0/dbhome_1)(SID_NAME=RACTEST1))
)


node2:RAC= 
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = rac2vip.test.com)(PORT = 1529))
)




SID_LIST_RAC=
(SID_LIST=
(SID_DESC = (ORACLE_HOME =/dbfs/app/oracle/product/11.2.0/dbhome_1)(SID_NAME=RACTEST2))
)




3,  参数：
node1:
SQL> show parameter local_listener
NAME     TYPE VALUE
------------------------------------ ----------- ------------------------------
local_listener     string RAC1_LOCAL


SQL> show parameter remote_listener
NAME     TYPE VALUE
------------------------------------ ----------- ------------------------------
remote_listener     string racscan.test.com:1521


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


node2：
SQL> show parameter local_listener
NAME     TYPE VALUE
------------------------------------ ----------- ------------------------------
local_listener     string RAC2_LOCAL


SQL> show parameter remote_listener
NAME     TYPE VALUE
------------------------------------ ----------- ------------------------------
remote_listener     string racscan.test.com:1521


4，参数文件：
pfile:
[oratest@rac1 dbs]$ cat initRACTEST1.ora
spfile='+DATA/RACTEST/spfileractest.ora'


[oratest@rac2 dbs]$ cat initRACTEST2.ora
spfile='+DATA/RACTEST/spfileractest.ora'
根据pfile创建spfile:
create spfile='+DATA/RACTEST/spfileractest.ora' from pfile;


5, 参数修改命令:
alter system set local_listener='RAC1_LOCAL' sid='RACTEST1' scope=both;
alter system set local_listener='RAC2_LOCAL' sid='RACTEST2' scope=both;

网页题目：OracleRAC和SCAN同时对外提供服务的配制方法
标题来源：http://myzitong.com/article/gpehcp.html