hadoop2.0中的ha与secondary namenode需不需要另起一台服务器

hadoop2.0中的ha与secondary namenode需不需要另起一台服务器
1.2 HDFS2.2.0HA配置
1.2.1 core-site.xml


fs.defaultFS
hdfs://mycluster



io.file.buffer.size
131072



hadoop.tmp.dir
/opt/hadoop/data/hadoop/temp
Abase for other temporarydirectories.



hadoop.proxyuser.hadoop.hosts
*



hadoop.proxyuser.hadoop.groups
*



ha.zookeeper.quorum
192.168.111.130:31315,192.168.111.131:31315,192.168.111.132:31315



ha.zookeeper.session-timeout.ms
1000
ms