It sounds like the job was successfully submitted to the cluster, but there
as some problem when starting/running AM, so that no progress is made. It
happened to me once, when I was playing with YARN on a cluster consisting
of very small machines, and I mis-configured YARN to allocated to AM more
memory than the actual memory available on any machine on my cluster. So
that RM was not able to start AM anywhere due to inability to find big
enough container.

Could you show the logs from the job? The link should be available on your
console after you submit a job e.g.
13/12/10 10:41:21 INFO mapreduce.Job: The url to track the job:
2013/12/10 Silvina Caíno Lores <[EMAIL PROTECTED]>