I'm running ambari 2.1.0. I tried to move the App Timeline Server (ATS) and the process failed (for various reasons).
I was able to bring ambari back up, but now it seems to think it has two ATS masters. In order to get things operational, I've put one of them (the one I was trying to move the service to) in maintenance mode and started the original one. Now I have a permanent alert on the first host that it failed to connect to the ATS on the second host.
From the dashboard, YARN appears to be up/operational but I'm not sure if it is or not.
Any suggestions on how I might be able to untangle this?
sorry if you saw the rest of the activity on this response. First, I posted the resultant output, but I did it as an answer. Given that it wasn't, I deleted it noticing only too late that I could have converted it to a comment. The next time I attempted to add the output, I managed to grab the wrong copy buffer (and wound up duplicating the original informational output from the GET command. So, I deleted that. Sigh.
Awesome. If you could "accept" my answer, that would be great. AMS crashing issue might be due to the version of Ambari you are using (2.1.0 is quite old and there have been numerous stability improvements on AMS since then). If it is possible, I highly recommend you upgrade to Ambari 2.4.2.