hadoop-hdfs-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Doug Balog <doug.hdphdfs...@dugos.com>
Subject Question about hadoop namenode -format -clusterid <clusterID>
Date Thu, 12 May 2011 03:03:37 GMT
I'm at the hackathon in SF just trying to setup a single node cluster from my trunk checkout.
I'm at the point where I need to format a new namenode, and the old way of 
just running "hadoop namenode -format" is failing because I'm not specifying a clusterID.

So I started poking around the code to try and figure what is expected for the clusterID
and I found that the namenode had a hidden option "-genclusterid" which
causes the namenode to just print out a new clusterID and exit. 
I say hidden because if you run "hadoop namenode -usage" its not one of the listed

What is the correct way to format a namenode now (in trunk) ? 
The current documentation doesn't match what the code does, 
so its unclear to me how this is supposed to work.

IMHO   "bin/namenode -format" should automaticlly generate a clusterID for you and
it should exit with an Exception. This is what everybody has been trained to do.
The only time you should have to specify a  clusterID is when you want to 
add a namenode to an existing cluster.


View raw message