前些天在虚拟机上搭建完RAC后,便想尝试测试一下Oracle TAF(透明应用故障转移)和负载均衡两大功能。
前些天在虚拟机上搭建完RAC后,便想尝试测试一下Oracle TAF(透明应用故障转移)和负载均衡两大功能。
1、负载均衡
我先在服务器端编辑tnsnames.ora文件,在orcl服务中添加LOAD_BALANCE = yes,内容如下:
然后把此文件下载到本地instantclient安装路径,通过sqlplus打开多个会话,发现这些会话随机分配到不同的实例上,请见下图:
2、透明应用故障转移
执行DBCA进入Service Manager,配置故障转移服务orcltest,选择两实例作为“首选实例”(orcl1为“首选实例”,orcl2为“可用实例”,也可以达到此目的),TAF 策略选择“ Basic”,,请见下图:
查看tnsnames.ora文件,发现多了orcltest服务,增加了FAILOVER_MODE参数,然后编辑本地tnsnames.ora文件,增加orcltest服务,内容与服务器一样。请见下图:
在客户端上同时打开两个会话连接到不同节点,关闭RAC1数据库后,连接到此节点的会话已经转移到RAC2上面。

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