---------- Forwarded message ----------
From: Sean Bigdatafun <sean.bigdata...@gmail.com>
Date: Wed, Jun 23, 2010 at 11:53 PM
Subject: dfs.data.dir and "hadoop namenode -format"
To: hdfs-u...@hadoop.apache.org
Can someone tell me what "hadoop namenode -format" does under the hood?
I have started my HDFS cell with the following configuration.
-------------------
dfs.data.dir
/opt/hadoop/data
--------------------
Overtime, I want to add another directory as the data.dir, how can I achieve
it?
1) Can I simply edit "dfs.data.dir" in the hdfs-site.xml without stopping my
cell?
2) If 1) is not legitimate, can I run "stop-dfs.sh", then do 1) and then
"start-dfs.sh"?
3) My last question here is what "hadoop namenode -format" does. If I run it
on my Namenode, does it clean up the data.dir? and do I need to manually
clean up the data.dir on Datanode?
Thanks,
Sean
