[cisco-voip] IP Phone sets TFTP server to 255.255.255.255

[Ed Leatherman]

Hello,

Anyone run into this before?

I have a number of IP Phones that are reporting tftp errors in syslog.
Around 60 of them, so far all the ones i've looked at have TFTP server
and TFTP Server 2 as 255.255.255.255 according to the phone's web
interface. They are all running 8-3-5 and are prevented from upgrading
to the default load (9-0-3) due to their TFTP server being wrong. They
are located in different IP Subnets/Routers.

A packet capture from our core shows DHCP ACK's going back to the
phones with the correct option 150 OR option 66 (i've tried both now).
I also changed some innocuous settings like DNS servers to verify that
the phones were getting live DHCP, which they were.

We use Infoblox for DHCP, so I tried to move one of the ranges
(stadium pressbox that isn't in use for a week or so). I moved the
DHCP range to its router:
ip dhcp pool phonetest
   network 10.x.y.128 255.255.255.192
   default-router 10.x.y.129
   option 150 ip a.b.c.d
and some excludes to take care of HSRP interfaces. No luck, same
symptoms on the phones.

Now, if I go and manually set the TFTP server from the phone,
everything's happy, and it upgrades. After upgrade it appears to have
no trouble reading the option fields.

Would rather not visit 60-some phones to manually fix them.. is there
a way to force the TFTP server remotely other than DHCP?

Thanks for any advice!

-- 
Ed Leatherman