PC(1) is a mobile user.
PC(2) is a gateway which has two interfaces WAN and LAN.
WAN connects to internet, and LAN connects to local PCs which have private IP.
PC(1) wants to connect to PC(3) using L2TP tunnel.
After the L2TP tunnel established successfully between PC(1) and PC(2), PC(1) can ping PC(3) successfully.
However, it fails when the packet size is huge (i.e. ping -l 1000 IP_of_PC(3)).
So, I use tcpdump on LAN, find that the ICMP echo request is sent to PC(3) and PC(3) sends the ICMP echo reply to PC(1).
But when I use tcpdump on WAN, the udp packet corresponds to ICMP echo reply does not appear.
I think it is the problem of L2TP server instead of PPPD, because I can do the same thing successfully while I use PPTP tunnel.
(i.e. the configurations of pppd are the same when it is called by L2TP and PPTP).
What's wrong?
Thanks,
-Derek
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Hi,
Below is the environment:
PC(1) is a mobile user.
PC(2) is a gateway which has two interfaces WAN and LAN.
WAN connects to internet, and LAN connects to local PCs which have private IP.
(1) [WinXP L2TP client] --------------------------(2)[NetBSD L2TP server]------(3)PC
PC(1) wants to connect to PC(3) using L2TP tunnel.
After the L2TP tunnel established successfully between PC(1) and PC(2), PC(1) can ping PC(3) successfully.
However, it fails when the packet size is huge (i.e. ping -l 1000 IP_of_PC(3)).
So, I use tcpdump on LAN, find that the ICMP echo request is sent to PC(3) and PC(3) sends the ICMP echo reply to PC(1).
But when I use tcpdump on WAN, the udp packet corresponds to ICMP echo reply does not appear.
I think it is the problem of L2TP server instead of PPPD, because I can do the same thing successfully while I use PPTP tunnel.
(i.e. the configurations of pppd are the same when it is called by L2TP and PPTP).
What's wrong?
Thanks,
-Derek