The solution ended up not being Meraki-related, but I'd like to include it in case anyone in the future comes looking for help:   Temporarily, to get the APs to communicate on the proper VLAN and DHCP scope, I set up DHCP reservations and then assigned a static IP in Meraki Dashboard to each AP matching the reservation. I was then able to untag the ports with the proper VLAN and have it all work. This gave me a working network while I figured out the actual cause. When I plugged in a laptop to a port on the WiFi VLAN, I got a 10.x.x.x/8 address with a gateway of 10.128.128.128. This is a Meraki Cloud DHCP, so this indicated that the VLAN was not communicating at all with the DHCP it was supposed to be. Said DHCP server is offsite; the culprit ended up being the DHCP relay in our firewall. Once I rebooted that and made sure that the switch the firewall was wired to had OSPF "redistribute connected. restrict [our DHCP IP and subnet mask]" and VLAN [WiFi] IP address [Our DHCP IP and subnet mask], I was able to remove the DHCP reservations and set the APs back to DHCP in Meraki Dashboard.   Hopefully this helps some folks in the future, and thanks everyone who replied for your suggestions! The key troubleshoot that led to the breakthrough was the suggestion of using a laptop to connect to the VLAN/DHCP. ... View more