I've had the Bad DNS error happen a few times, though I don't recall ever seeing it also say disabled switch. That doesn't seem right.
In my cases the switch has always remained functional and passed traffic.
The error is produced when the some or all of the DNS checks in the connectivity monitor fail. This KB is for the MX, but a lot of it applies to the other devices as well as they are also probing for connectivity to the cloud:
This is an OLD post, but I wanted to add my own experience with Disabled Switch (Bad DNS). The Error, is just a bad Error, written poorly by Meraki Programmers. It leaves the engineer with no real guidance as to whats wrong, not where to look.
In my Case, my customer moved their switches from DHCP to Static, When they did that, some of their switches ended up with Duplicate IPs. The duplicated IP switches remained "online" in the dashboard, and showed "disabled Switch Bad DNS". Even Cisco Switches in their logs show "Duplicate IP". What can't Meraki do the same and give a clear log entry for it. Any way if your reading this, everything everyone else is saying here is definitely worth checking, but in my case it was duplicate, IPs. Make sure the management IPs of your gear is not duplicated anywhere.