I'm switching our VoIP phones (Polycom 301s and 501s) to our data network. They were previously segmented to their own network. This means disabling the DHCP on the Trixbox (Asterisk) server and configuring the Sonicwall TZ 210 DHCP to indicate that Trixbox is the TFTP server.

The Polycom phones are stating "could not contact boot server". All phones are configured to TFTP and were confirmed working when previously using the Trixbox server for DHCP. Trixbox DHCP is now turned off.

I've configured options 66(as String), 128(as IP) and 150(as IP) in DHCP and added them to a TFTP Option Group. I've enabled "Allow BOOTP Clients to use Range" for the Dynamic IP range and assigned the Option Group TFTP as the DHCP Generic Option Group.

Any idea what I'm missing? Is there a separate tool to inspect the DHCP response to compare Trixbox to the Sonicwall?