Oracle 11g RAC客户端使用SCAN IP无法连接问题

Oracle 版本：11.2.0.1.0

客户端：Windows Server 2003/PLSQL Developer

Oracle服务器端的ip设置如下：

##公网ip
192.168.135.201 WIN-2008SERVER1
192.168.135.202 WIN-2008SERVER2


##虚拟ip
192.168.135.211 WIN-2008SERVER1-vip
192.168.135.212 WIN-2008SERVER2-vip


##私网ip
10.168.135.201 WIN-2008SERVER1-pri
10.168.135.202 WIN-2008SERVER2-pri

##SCAN ip
192.168.135.220 scan

两个RAC实例的虚拟ip已经设置为ip地址而不是名称，如下：

客户端PLSQL Developer的tnsnames.ora设置如下：

ORCL = (DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.135.201)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.135.202)(PORT = 1521))
(LOAD_BALANCE = yes)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
(FAILOVER_MODE =
(TYPE = select)
(METHOD = basic)
(RETRIES = 180)
(DELAY = 5)
)
)

scan =

(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = scan)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)


192.168.135.200 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.135.200)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)

使用PLSQL Developer连接ORCL，没有任何问题。

客户端Windows的hosts文件没有修改之前，使用PLSQL Developer连接Oracle的SCAN ip 192.168.135.200，异常如下：

ORA-12541: TNS: no listener

连接Oracle的SCAN名称scan，异常如下：

ORA-12545: Connect failed because target host or object does not exist

网上有说升级Oracle版本就可以解决的，没有尝试过，不知道可否？

也有说将RAC实例的local_listener修改为虚拟ip就可以的，但是已经是这样了，不知为何？

最后，客户端Windows的hosts文件添加Oracle服务器端的虚拟ip和SCAN ip的设置，重启操作系统之后，使用PLSQL Developer连接Oracle的SCAN名称scan，连接成功！

扩展话题：如果SCAN名称直接设置为ip地址（不知Oracle是否支持？），客户端PLSQL Developer连接的host名称也就可以填写为ip地址了，这样看起来就和连单机Oracle实例很像了。

扩展阅读：

ORA-12541: TNS:no listener ( ERROR coming when one node of RAC database is off

http://www.dbasupport.com/forums/showthread.php?53938-ORA-12541-TNS-no-listener-(-ERROR-coming-when-one-node-of-RAC-database-is-off

java应用连接oracle 11g R2 rac (用scanip连接报错)

http://blog.csdn.net/weiwangsisoftstone/article/details/38535463

11gR2 clients connect to the database using SCANs

http://www.dbatoolz.com/t/11gr2-clients-connect-to-the-database-using-scans.html

scan-ip部分可以连接，部分连接不了

http://t.askmaclean.com/thread-4090-1-1.html