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 options. 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. Doug
