HI all, I was once stung by issue of DNS not working correctly on a Hadoop/Hbase cluster, it wasn't easy to debug.
So I wrote a simple utility to verify DNS on a cluster (all machines) https://github.com/sujee/hadoop-dns-checker - It is written in pure Java; doesn't use any third party libraries. So it is very easy to compile and run. - it does both IP lookup and reverse DNS lookup - will also check if machine's own hostname resolves correctly - it can run on a single machine - it can run on machines across cluster (using password-less ssh) Hope some one else finds it useful. Any feedback and comments most welcome. thanks Sujee http://sujee.net
