Disabled Switch (BAD DNS)

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Disabled Switch (BAD DNS)

Hi All,

 

I'm seeing the alert 'Disabled Switch (BAD DNS)' under the connectivity status on my MS250 switches. This occurs a couple of times a week, however, I dont know why and what the impact is.

 

Does anyone know why this error is produced, and more importantly, what does is mean by 'Disabled Switch'? Does this mean that traffic flow is being impacted?

 

Thank you

 

3 REPLIES 3
jdsilva
Kind of a big deal

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:

 

https://documentation.meraki.com/MX/Firewall_and_Traffic_Shaping/Connection_Monitoring_for_WAN_Failo...

 

 

Ok, thanks for the reply. I will keep any eye on this and see if it actually causes an issue as the error is a little confusing.

RobinsonRoca
Getting noticed

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.

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