I've been reading and googling for the past week trying to wrap my head around the Cisco IP Phone TFTP upgrade process. The effort has been to try and make a Cisco 7941G work with Asterisk. This process has been documentended well in many places and I've followed several guides. The issue I am having is the Phone in questino never seems to ask or make TFTP connection even though it is getting the correct information from the DHCP option 150.
Doing a Wireshark, I see the Cisco phone ask for a DHCP information, I see the DHCP return an Offer and the Phone accept it. I then see the Phone issue a few ARP requests for the location of the TFTP server, but after that. Nada. One thing that is alarming or I've notice is ICMPv6 Router Solicitation datagrams seem to show up and then are immediately followed by the Phone rebooting again and again.
Other notes:
I've verified the TFTP server is working and logging via a TFTP client attached to the same Subnet.
- I've verified the phone can be upgrade. Via a know working
environment using Cisco Call Manager, the Phone pulled down the
firmware correctly. - I've tried doing the Soft reset # 123456789*0# and the Hard reset to
format the flash # 3491672850*# - I never see anything in the TFTP server logs, even though I've used a
TFTP client to verify the verbose level - Is CDP or LLDP involded at all with the phone upgrade process? I see
a lot of those messages, even when running it through a hub and not a
switch. - Weird thing is, I plug in a Cisco 7945G phone and it accepts the
option 150 and pulls down the firmware files and configs.
Screenshot of Capture:
Best Answer
Option 66 is "boot server", and has worked on every cisco ipphone I've plugged in. As you only have one server, 150 isn't necessary unless there are other "network boot" services... (everything listens to 66, cisco's listen to 150)
The way I've always dealt with this is to have a dedicated, isolated network for setting up phones. The DHCP server provides IP setting for this network and a tftp server via option 66. Reset the phone and clear network setting. It then restarts and goes through the whole shebang. The only phone that was ever a problem had been locked to a call manager -- with an unknown to us password. (extra steps were required to clear it. if it had be "secured", it would've been trash -- see also: CTL files, and encrypted configs.)
I'm not familiar with the 41G, but the 40 has a diag serial port on it. It might emit an error message -- but it's been a while since I messed with that diag port.