This alert means a bad static IP or an incorrect VLAN tag with DHCP is being assigned to the Meraki hardware. Typically, network hardware will simply not work if you assign a bad IP address to it. Meraki hardware, however, will automatically switch back to DHCP (automatic IP assignment) so that it can check in to the cloud and alert you about the problem if at all possible.
The most common causes of this error message are:
The device has had a working static IP, but network changes have caused the IP address to become invalid.
A typo or otherwise incorrect value while assigning a static IP in the app.
The wrong VLAN tag is used for DHCP.
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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