在ORACLE RAC 环境下，为了做到高可用性，需要对客户端的tnsnames.ora这个文件进行配置。以下所示为配置示例
XJSK =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.13)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.14)(PORT = 1521))
)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = xjsk)
(INSTANCE_NAME = xjsk1)
(INSTANCE_ROLE = PRIMARY)
(FAILOVER_MODE =
(BACKUP = XJSK_BACKUP)
(TYPE = SELECT)
(METHOD = BASIC)
(RETRIES = 30)
(DELAY = 5)
)
)
)
XJSK_BACKUP =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.14)(PORT = 1521))
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.13)(PORT = 1521))
)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = xjsk)
(INSTANCE_NAME = xjsk2)
(INSTANCE_ROLE = PRIMARY)
(FAILOVER_MODE =
(BACKUP = XJSK)
(TYPE = SELECT)
(METHOD = BASIC)
(RETRIES = 30)
(DELAY = 5)
)
)
)
在以上示例中所标红色部分为TNS的别名及备份TNS别名，可按用户应用的需要自行修改。
在以上示例中所标蓝色部分，分别为RAC数据库的服务名和各节点的实例名，可按节点数量的不同及服务名的不同自行修改。