question Re: Moving Secondary NameNode Checkpoint directory in Archives of Support Questions (Read Only)

Moving Secondary NameNode Checkpoint directory

awatson — Thu, 22 Oct 2015 23:37:32 GMT

Hi,

The Secondary NameNode (SNN) checkpoint directory at /tmp/hadoop/hdfs/namesecondary is filling up tmp and I would like to move it. What is the best way to do this? Also once moved, can I just RM -R all data in the old directory or do I need to copy it over?

Thanks,

Re: Moving Secondary NameNode Checkpoint directory

smohanty — Thu, 22 Oct 2015 23:44:51 GMT

From Ambari perspective, if you stop HDFS, modify the config property shown below, move all content to the new location it will likely work.

Someone from HDFS team can confirm if there is any affinity to the actual folder path.

<property>
      <name>dfs.namenode.checkpoint.dir</name>
      <value>/hadoop/hdfs/namesecondary</value>
</property>

Re: Moving Secondary NameNode Checkpoint directory

sluangsay — Fri, 23 Oct 2015 00:40:41 GMT

Apart from the fact that the partition is getting full, the main reason I see to move the checkpoint directory is that you cannot trust that the data under /tmp won't be wiped out after a reboot of your server.

In general, avoid putting any kind of Hadoop information (data or metadata) under /tmp, unless you are sure this is kind of temporary or non critical information.

Re: Moving Secondary NameNode Checkpoint directory

ArpitAgarwal — Mon, 26 Oct 2015 03:00:13 GMT

HDFS has no affinity to a specific path for this setting.