VPN split access anyone?

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freitasm

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Topic # 114442 20-Feb-2013 08:32

I am playing with a SSTP VPN access and have a problem accessing the Internet while connected to the VPN.

The server won't route access to the Internet (and I don't want it to do it) which means that while connected to the VPN the client PC can access resources in the LAN but can't access the Internet. If I uncheck the advanced option in the IPv4 settings to not use the Gateway by default then I have Internet access but can't access the VPN resources.

Does anyone have a suggestion to fix this and have access to both resources while the VPN is connected? Something that wouldn't break things when the VPN is not active?

I am running the SSTP VPN server on a Windows Server 2012.

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RunningMan

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Reply # 766177 20-Feb-2013 08:37

Were you using a Cisco SRP521? The current firmware has a VPN server in it that you could try instead, if this is at the same site.

freitasm

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Reply # 766178 20-Feb-2013 08:39

No, the servers are at the datacentre. I have a SRP521 but this is on my client side, so no use there.

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magu

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Reply # 766180 20-Feb-2013 08:39

Seems like you need to add a route for the LAN subnet on the other side of that VPN link on your own machine.

Something like (pseudo code):

ROUTE ADD 192.168.0.0/24

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freitasm

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Reply # 766181 20-Feb-2013 08:42

Yes, I guess would need to add a route to the VPN on my client. I will probably need to change some of the stuff on my server side too as the server LAN uses the same subnet as my client LAN, so I don't want to mess up the addresses.

Right, will have to work a bit on this...

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kiwirock

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Reply # 766199 20-Feb-2013 09:10

Yeah they won't work to well having the same subnet.

Another pet annoyance I've found with VPN's on Windows (at least XP and below, I don't have 7), that if your remote subnet is say 10.1.1.X/24 silly Windows still puts a route in for a /8 instead on the PPP/VPN interface based on the old class system. This is annoying especially when using say 10.0.0.X/24 as it'll put a route in for 10.X.X.X/8 instead and cause headaches if your local LAN is any address starting with 10 until you manually delete the route and put a /24 in.

edit: Was referring to the client side.

freitasm

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Reply # 766201 20-Feb-2013 09:11

Yes, later today I will change the Hyper-V Private Network configuration to a different subnet, reconfigure the VPN server, add a route to that and work from there...

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magu

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BitSignal

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Reply # 766202 20-Feb-2013 09:13

I've found using the 172.16.x.x range being extremely helpful to avoid such problems, especially when connecting to multiple VPN endpoints at the same time.

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kiwirock

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Reply # 766215 20-Feb-2013 09:24

Yes those 172.16/12 addresses are handy, I use them on my WiFi subnets as chances are someone who connects doesn't use them.

I was using the commercial NAT reserved range for a while added not that long ago but switched back to 172 since IPv4 is now on the thin line.

freitasm

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Reply # 766270 20-Feb-2013 10:43

Ok, changed the range in the server side from 192.168.2.x to 192.168.10.x and changed option on VPN server configuration to "Enable this computer as a [x] IPv4 router (O) LAN routing only".

This fixed the issue with no need to add any new routes on the client side. I can now continue to access the Internet and have access to the LAN on the server side.

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