Best Practices for Upgrading Hadoop Version?

[Eli Finkelshteyn]

Hi,
I'd like to upgrade my Hadoop cluster from version 0.20.2-CDH3B4 to 
1.0.3. I'm running a pretty small cluster of just 4 nodes, and it's not 
really being used by too many people at the moment, so I'm OK if things 
get dirty or it goes offline for a bit. I was looking at the tutorial at 
wiki.apache.org <http://wiki.apache.org/hadoop/Hadoop_Upgrade>, but it 
seems either outdated, or missing information. Namely, from what I've 
noticed so far, it doesn't specify what user any of the commands should 
be run as. Since I'm sure this is something a lot of people have needed 
to do, Is there a better tutorial somewhere for updating Hadoop version 
in general?

Eli