Manuel Bouyer wrote:
> On Thu, Dec 16, 2004 at 09:37:08AM +1100, J. Piers Hearn wrote:
> 
>>>Looks like an MTU issue. Make sure you have
>>>net.inet.tcp.rfc1323=0
>>>net.inet.tcp.mss_ifmtu=1
>>>in /etc/sysctl.conf
>>>
>>>-- 
>>>Manuel Bouyer <bouyer@antioche.eu.org>
>>>     NetBSD: 26 ans d'experience feront toujours la difference
>>
>>Changed those settings, everything working perfectly now! Out of
>>curiosity, exactly what are those two settings doing?
> 
> 
> The problem is to have TCP advertice an appropriate segment size to the remote
> end, so that individual packets won't exeed the MTU of the link (as
> something on the path is lowering the MTU without fragmenting).
> net.inet.tcp.mss_ifmtu=1 tells TCP to use the outgoing interface's MTU 
> as the maximum fragment size instead of some internal value.
> net.inet.tcp.rfc1323=0 turns off a TCP option which increase the lengh
> of the TCP header, and cause problems in this case (because it's not accounted
> in the MSS).
> 

In layman's terms (IIRC), the packets were getting chopped up along the way and not getting put back together properly. So, the settings are telling your machine to negotiate with the machine it's talking to and use packets of the proper size.

The max file size that you could transfer in the past should give you a hint as to what your MTU is normally set to (probably 2048, since you claim 1-2KB files worked).

-Tim