Hi,
 
I am using Grandstream phones on a LAN behind a Soekris4521 (NAT) running
M0n0Wall v1.2b3 connecting to the internet via ASDL-PPPOE.
M0n0Wall works fine except that the TFTP file download (firmware refresh of
the phones from an outside TFTP server).
 
The phone can't download any of the files (I can see in the TFTP server's
log that the phone connects but the transfer doesn't start). It looks for me
that the UDP packages from the TFTP server can't pass my router.
 
I tried it with two other routers (linksys, cisco) and the TFTP transfer
worked with them.
 
There is no rule set up which blocks the traffic in M0n0Wall.
 
I really like M0n0Wall so I would be happy if anyone could help to resolve
this problem.

Is there any way to establish a TFTP file transfer through M0n0Wall?
 
Sincerely
Gabor Riesz