[OpenAFS-devel] Rx and MTU fun

[aeneous@speakeasy.org]

> This is on my list of things to look at, but looking at the code briefly 
> it doesn't look like Rx will even decrease the MTU once it's increased it;
> I am a regular user of a network with a VPN tunnel between groups of
> machines, and the tunnel MTU is lower than the ethernet MTU (1500) on
> either side. Trying to access AFS through the tunnel is problematic in
> that certain RPCs never complete and hence things are unusable. 
> 
> Does this sound familiar to anyone?

RX won't decrease the MTU below 1500, for sure.  But doesn't IP fragment and 
reassemble packets for you?  Oh, I'll bet you've got a firewall rule 
discardiing IP fragments.  Hmp.