(intermittent failure on ec2 host) HttpHostConnectException: Connect to localhost:31815 failed: Connection refused

We have scripts that instantiate an ec2 instance dynamically, then we start our application running on them and our webdriver tests also running on same box, testing against localhost:9080. So this all works most of the time, many times a day. However a couple times I noticed midway thru the run (after an hour) a couple tests fail, with the exception from the title. At the time, the selenium test is trying to manipulate the browser window (actual chrome app, not simulator), and a couple tests fail. Then 2 minutes later, magically everything returns to normal and passes. We have had some DNS problems with our network, am wondering if it could effect it, however it seems unlikely given we have tests that are pointing back to itself (localhost). If this exception happens I could potentially catch it and do something - what would you do, to troubleshoot? Likely I won't find it as it happens, as the instances get deleted soon after.