Why not just attach a debugger from an IDE (with the right hadoop sources)
to DN JVM?
On Thu, Mar 8, 2012 at 1:16 AM, Evert Lammerts <[EMAIL PROTECTED]>wrote:
> Hi list,
> I've spent the whole of yesterday debugging a DN to find and fix a trivial
> bug (HDFS-3059). Difficulty is that we have Kerberos enabled and I didn't
> know how to emulate that environment locally. So what I did was editing the
> source, building the jars, deploying them on my NN and a single DN,
> starting deamons, and looking at my debug statements.
> Obviously not the most optimal way. How do you debug deamons with Kerberos
> enabled? Do you add your development machine to the cluster, give it a
> principal, and configure the network? Any tips / best practices? I expect
> we're going to need this more often since we're just bringing up a fair
> sized multi-tenant production environment (~70 machines) and I guess this
> won't be the only time we'll want to see what exactly happens.