Spark 1.6.0 web console shows a running application in a "waiting" status, but it's actually running. Is this an existing bug?

I have 2 questions/issues. 1. We had the spark-master shut down (reason unknown) we looked at the spark-master logs and it simply shows this, is there some other log I should be looking at to find out why the master went down? 16/09/05 21:10:00 INFO ClientCnxn: Opening socket connection to server

spark 1.6.0 web console shows running application in a "waiting" status, but it's acutally running

I have 2 questions/issues. 1. We had the spark-master shut down (reason unknown) we looked at the spark-master logs and it simply shows this, is there some other log I should be looking at to find out why the master went down? 16/09/05 21:10:00 INFO ClientCnxn: Opening socket connection to server