Annoying VPN Issue

[shab]

Hi Everyone,

I get error 721 (Remote computer did not respond) whenever I try
connecting to my XP machine at home through vpn.

The server machine is behind a D-Link(di-624) router and the client is
behind a Linksys(WRT54G) router. I checked both routers to ensure that
IPSec, PPTP and L2TP Passthrough were enabled and they indeed are. On
the server side, ports for the IPSec and PPTP are forwarded to the
correct machine as well. The funny this is that the first 2 times I
tried this, the connection worked flawlessly!. After the second
connection, I opened a remote desktop connection to the server and
after that I started getting the error message. Am I missing something?

I restarted both machines, removed and readded connections on both
sides and still no change. I checked the dlink log and the only odd
thing i notice is that I keep getting messages like this "Smurf Attack
Detect 192.168.0.1:8 192.168.0.1:0 Packet Dropped"

Any help would be greatly appreciated!

Thanks,

Moe

 

[Robert L [MVP - Networking]]

It could be GRE issue. try to use PPTPsrv and PPTPclnt test it.

VPN troubleshooting tools VPN Troubleshooting Tools. 1. PPTPclnt and PPTPsrv to test GRE and PPTP. 2. IPCONFIG to troubleshooting connection and name resolution issues ...
www.chicagotech.net/vpnissues/vpntools.htm


Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
Hi Everyone,

I get error 721 (Remote computer did not respond) whenever I try
connecting to my XP machine at home through vpn.

The server machine is behind a D-Link(di-624) router and the client is
behind a Linksys(WRT54G) router. I checked both routers to ensure that
IPSec, PPTP and L2TP Passthrough were enabled and they indeed are. On
the server side, ports for the IPSec and PPTP are forwarded to the
correct machine as well. The funny this is that the first 2 times I
tried this, the connection worked flawlessly!. After the second
connection, I opened a remote desktop connection to the server and
after that I started getting the error message. Am I missing something?

I restarted both machines, removed and readded connections on both
sides and still no change. I checked the dlink log and the only odd
thing i notice is that I keep getting messages like this "Smurf Attack
Detect 192.168.0.1:8 192.168.0.1:0 Packet Dropped"

Any help would be greatly appreciated!

Thanks,

Moe

 

[shab]

Hi,

I tried the tools you suggested. On the client side, the connection is
established and the packets are sent, however or the server side, the
program keeps waiting for GRE packets and never receives any. When I
start PPTsrv I get the following error message:

ERROR 10048 binding socket:
WSAEADDRINUSE: Address already in use


I check my router firewall settings I have the following for VPN in
firewall:

Allow IPSec WAN,* LAN,192.168.0.2 UDP,500
Allow IPSec_ESP WAN,* LAN,192.168.0.2 ESP,
Allow PPTP WAN,* LAN,192.168.0.2 TCP,1723
Allow PPTP_GRE WAN,* LAN,192.168.0.2 GRE,

The specific settings for VPN have also been enabled as I mentioned
above. I also have the latest fimware.

 

[shab]

If anyone is interested I obtained a solution from tech support;

1. Reflash the latest firmware, even if it is already up to date.
2. Perform a hard reset (Hold reset for 10 seconds)
3. Enter in settings again.

Thanks,

 

[Robert L [MVP - Networking]]

Thank you for the update.

Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
If anyone is interested I obtained a solution from tech support;

1. Reflash the latest firmware, even if it is already up to date.
2. Perform a hard reset (Hold reset for 10 seconds)
3. Enter in settings again.

Thanks,