New public IP not being recognized by Meraki DDNS

[G_Colby]

Hello, all-

So yesterday my ISP scrambled my life by giving a new IP address to our cable modem; static IPs are not an option where I am.

My network has 3 MX65s. The device with the new public IP still shows the OLD public IP on the Appliance Status page, under WAN1 heading. This change happened 24 hours ago. The device has been rebooted several times, as have the other two devices on the network. The WAN1 address still has not updated.

It is my understanding that my Meraki should be 'checking in' to the cloud about every 15 to 30 minutes, at which point Meraki would recognize that there is a different IP and should update. Failing that, a reboot should propagate the change. This is NOT happening.

I can ping the hostnames of my other two devices and they work fine. The dynamic-m.com DDNS service has the correct public IP of those two devices. A ping of the hostname for the bad device times out.

What am I missing? Is there a way to force the system to detect that I have a new public IP? 

Thanks in advance

[MerryAki]

Could you verify the IP using ipinfo.io or something else?

Another thing why you can’t ping it is a missing port forwarding?

Did this ICMP check of your third location worked before?

I had same topics with Unitymedia/Liberty Global and nowadays Vodafone.

[G_Colby]

Yes, I did verify the IP address. Funny thing is, when I try to ping my IP from a remote location, the ping times out.

The third location worked fine for the first week, but as soon as the IP address got switched up, everything has gone south. I'm assuming this is because of the change and the inability for the outside world to even REACH my current IP of the third location.

[OVERKILL]

If there was no route to your new IP, you'd have no internet on that device. Are these straight-up modems or is it possible that the device got reset and is now in modem/gateway mode? Even if the external routable IP didn't change in that scenario (Appliance Status -> WAN1 would still show the correct external IP) of course the MX would be unreachable, but could still get to the internet. What do you see under Appliance Status -> Uplink -> WAN1 ? 

[MerryAki]

So pinging the dynamic-m DDNS service times out or the IP address you enumerated?

When the config is 100% identical and ICMP is active, you should be able to ping those locations. As mentioned above I would try to reach the IP.

Have you contacted your ISP?

[PhilipDAth]

That is unusual.  I think I would give the cable modem a power cycle as well.

[LeeMT]

From the documentation, this may take some time to update:

https://documentation.meraki.com/General_Administration/Cross-Platform_Content/Device_Showing_an_Inc...

Have you tried performing a hard reset?