[高可用] 客户端 RAC TNSNAME 配置

rac =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = rac1-vip)(PORT = 1521))
      (ADDRESS = (PROTOCOL = TCP)(HOST = rac2-vip)(PORT = 1521))
      (LOAD_BALANCE = YES)
    )
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = racdb)
      (FAILOVER_MODE =
        (TYPE = SESSION)
        (METHOD = BASIC)
        (RETRIES = 180)
        (DELAY = 5)
      )
    )
  )