Hadoop NameNode backup

 

NameNode：
<property>
    <name>dfs.name.dir</name>
    <value>/home/hadoop/dfs/name,/mnt/hadoop-backup</value>
    <fi nal>true</fi nal>
</property>

/mnt/hadoop-backup 是SSN在NameNode的挂载点，NameNode同时将metadata写入/home/hadoop/dfs/name,/mnt/hadoop-backup中

当一个namenode失败的时候，you should moving the IP address, setting up a new backup node