I had a very similar issue. I have about 20 Meraki AP's across 5 sites. This morning, I added a new AP to one of the sites and within a few minutes I started getting email alerts that APs went down. I logged into the Meraki Dashboard which reported that about 75% of my AP's across all sites were offline, although, like yours, they were still accepting clients and passing traffic. After about 45 minutes, they all came back "online" on their own. They are all running 29.5.1   The really strange part is that the APs that were "down" were seemingly random. For example, I put eight new MR-46's in our airport this year. They were all purchased at the same time, have sequential Mac addresses, are all connected to the same network, and six of the eight reported as off-line. Weird wild stuff. ... View more