Wireless

[jmmckean]

Product: WZR-HP-G300NH

Firmware: 1.65

Internet Connection: PPPOE DSL

I have a new WZR-HP-G300NH setup for PPPOE DSL. Very basic config, no VPN server, no NAS setup, no port forwards, just basic internet connection. Whenever I connect to a PPTP vpn from OSX (Snow Leopard, not sure of the exact version number) it authenticates and connects fine, but will drop the connection the moment any data begins to pass through the VPN tunnel. I have multiple VPN servers, some linux, some windows but all of them have the same problem. I can connect with my windows machines without any problems. Also, I didn't have this issue with my old router (also a buffalo, forgot the model #), but it died so I had to replace it.  I can also connect directly to the DSL modem with my macbook and dial a VPN without any issues, so it does seem to me to be some kind of router or compatibity issue.

Where I live and work requires me to connect to various remote VPN servers. So this problem is quite frustrating.

[Colin137]

Make sure PPTP passthrough is checked in Security->VPN Passthrough.

[jmmckean]

Yes, PPTP passthrough is enabled, still no luck.

[jmmckean · Accepted solution]

Ok, so I stumbled upon a(the) solution. The default MTU setting was 1454 which I changed to 1492 (max for pppoe) and the problem went away. I am now happily browsing my VPN network on my mac.

Side Note:

In searching for a solution I came across a thread reply that mentioned it could possibly be a MTU missmatch, so I first tried lowering the MTU to 1450 then to 1400. When I lowered it to 1400 I began seeing the same behavior on my windows machines, so I went the other direction and raised it to 1492. I'm not entirely sure why this corrected it because my other routers are set at 1454 and they work???? Go figure. I'm happy it's working.

[Colin137]

That's.... really strange. I'm glad you found a solution though!