RAC优势和劣势
http://tech.it168.com/a2012/0814/1384/000001384756_all.shtml
双机热备与RAC并行模式对比 
WAS数据源设置
http://www.educity.cn/shujuku/553585.html
在WebSphere中配置配置Oracle RAC集群的数据源，假设Oracle RAC双击分别为 HOST1 与 HOST2 ， 端口为1521 ，服务名为 orcldbservice，则配置的URL连接串为
jdbc:oracle:thin:@(description=(ADDRESS_LIST=(ADDRESS = (PROTOCOL = TCP)(HOST = HOST1)(PORT = 1521))(ADDRESS = (PROTOCOL = TCP)(HOST = HOST2)(PORT = 1521)))(FAILOVER=yes)(LOAD_BALANCE=yes)(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = orcldbservice)))创建数据源之后，需要重启nodeagent ， 否则测试不会通过。
sqlplus plsql连接配置
http://blog.sina.com.cn/s/blog_4fe6d4250102v5fa.html
使用vip方式
infodb8 =
(DESCRIPTION=
(ADDRESS=(PROTOCOL= TCP)(HOST=138.*.1.81)(PORT= 1521))
(ADDRESS=(PROTOCOL= TCP)(HOST=138.*.1.82)(PORT= 1521))
(LOAD_BALANCE= yes)
(FAILOVER= ON)
(CONNECT_DATA=
(SERVER= DEDICATED)
(SERVICE_NAME= infodb)
(FAILOVER_MODE=
(TYPE=SELECT)
(METHOD= BASIC)
(RETRIES= 30)使用public ip方式
infodb8=
(DESCRIPTION=
(ADDRESS_LIST=
(ADDRESS=(PROTOCOL= TCP)(HOST=138.*.1.83)(PORT= 1521))
)
(CONNECT_DATA=
(SERVICE_NAME= infodb)
(INSTANCE_NAME= infodb1)
)
(HS = OK)
)都是收集来的，未经验证，备用~
