I'm experiencing an odd issue, and I was wondering if anyone in the community has seen this before.
We have Meraki MS-350 switches running firmware 14.33. We are using Yealink T48S VOIP phones with GoToConnect as our service provider. The desk phones are on a separate VLAN and DHCP is enabled on the VLAN.
After a recent desk phone firmware update, our desk phones are unable to successfully register with GoToConnect upon rebooting. I am able to ping the phone and access its web GUI from my desktop PC VLAN. The phone certainly appears like it is functioning normally on the network except for registering with the provider.
The workaround is to either set a static IP address on the phone or to reserve the IP address on the Meraki switch. If either of those things are done, the phone comes up and registers without a problem. If I remove the IP reservation and reboot the phone, it will grab another IP address and fail to register again. I cannot understand why this might be. My gut feeling is that this is a bug in the phone firmware, but the VOIP provider hasn't been able to nail this one down definitively.
Has anyone run across something like this? Is it generally best practice to reserve the IP addresses of desk phones on a VLAN? Any insight would be appreciated.
Thanks in advance!
Rich