Not sure if this a newer feature, as it's now about a month and a half after your post but, if it is a power outage it will show it on the relevant tooltip. Also it is better to select the last two hours for the graph so that you can dial in better on the specified outage. I came here today to figure out how to see the uptime, and though the answer I got is not what I was looking for it was very helpful for tracing the problem source.  ... View more