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IP Phone cannot reach external TFTP server on ASA5505

Hello all,


I have a small business customer where we deployed a HPBX phone system. The ASA is acting as the DHCP server for the data and voice vlans. Every PC and phone are functional. There is one phone that I had to assign a static IP since the ASA cannot do DHCP by MAC reservation.

I assigned the correct IP, GW, Mask and DNS servers ( / I also allowed access from the TFTP server into the firewall. The phone registers fine by contacting the SIP server, but it doesn't update its config since it cannot access the TFTP server. I ran several captures of the phone booting up and in response to the DNS query, I see "No such name". I am not sure what else I can try. Any ideas?


Thanks in advance,


Super Bronze

Hi, Not that familiar with



Not that familiar with VOIP related things.


I guess with the DHCP using phones the DHCP server gives them information with an "option" to which server they need to connect to? Is the staticly configured phone missing some configurations or is it configured to connect by DNS name and the configured DNS servers simply cant resolved that name to the actual IP address? Is it possible to configure the phone with the IP address directly to which to connect to?


Again I have to say I am not familiar this part of networking so above are just some things that came to my mind. It just seems to me that the if the DNS server replies with such a message then it simply does not have the required information about address the phone is trying to resolve.


- Jouni

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