[asterisk-users] Cisco 7940 Problem (Mess)

[Brian Candler]

On Tue, Sep 19, 2006 at 12:12:03AM +0900, Gary Guthary wrote:
> This is going to be an exercise in 'Networking' for sure.......
> 
> The only catch is that per the phone's network settings:
> 
> The phone uses a static IP of something like 192.168.0.220 with a Gateway of
> 192.168.0.1. - Standard class 'C' netmask (255.255.255.0).
> 
> The phone has DHCP DISABLED.
> 
> The phone has it's TFTP server set to something like 62.120.xxx.xxx
> (something completely outside of the local network).
> 
> My home LAN uses 10.0.0.xxx on the local side.
> 
> But I can reset my XP-Box to 192.168.0.99 and ping the phone with no probs.
> 
> But If I set my XP-Box to a static IP of the Phone's TFTP server, my
> 'SolarWinds' TFTP server sees nothing. - Figured as much as the phone's IP
> and my TFTP server's IP are not in the same 'net.
> 
> Bottom line. - I've got to figure out a way to build a 'mini-network' so the
> phone'll be happy but also set up a PC & TFTP with the same address that's
> set in the phone. - Perhaps I can fake-out the phone into thinking it's
> hitting a TFTP box on the Internet (????).

Set your TFTP server's IP address to be the phone's gateway address (i.e.
192.168.0.1), and add a loopback address on your TFTP server of
62.120.xxx.xxx. Then outbound packets will hit your machine, which will
believe that the address being contacted is itself, and it will answer.

I don't know how to do that with XP. Perhaps put in another NIC and
configure it as 62.120.xxx.xxx (and plug it into a hub so that it thinks the
cable is active)

Under Linux or FreeBSD you can use something like
  ifconfig lo:0 62.120.xxx.xxx/32
  ifconfig lo alias 62.120.xxx.xxx/32
respectively.

Maybe you can boot from an Ubuntu CD (this gives you a "live" Linux desktop
without reinstalling your system) and set up a tftp server there.

Debug using tcpdump (Linux/FreeBSD) or ethereal (Windows)

HTH,

Brian.