[Vpn-help] Problem with VPN and RDP

[Matthew Grooms]

Martin Zürcher wrote:
> Matthew Grooms wrote:
>> You could also try to reduce the MTU on your virtual adapter by a few
>> hundred bytes.
>>
> Done - but without success:-(
> 
> Any other idea?
> 

Have you tried using Wireshark to determine if RDP any packets reach the 
windows host? Usually when one type of communication works to a host but 
another type doesn't, its related to an MTU problem. The packet capture 
would show TCP setup occur, but all packets with large payloads would be 
missing. Sometimes a packet being sent, post encapsulation, exceeds the 
MTU of an intermediate link. In a perfect world, these packets would be 
fragmented and passed on but some devices will simply drop them. The end 
result is connection timeouts as you have previously described. Lowering 
the Virtual adapter MTU causes the inner IP packet to be smaller so that 
the final packet won't exceed the MTU, even with the additional headers.

-Matthew