We have three sites connected with LAN to LAN VPN's

Site A 192.168.100.0 255.255.255.0 (2860)
Site B 192.168.90.0 255.255.255.0 (2862)
Site C 192.168.80.0 255.255.255.0 (2862)

On site A and Site B there are servers with file shares. Users at Site A and Site B can access the file shares located on both sites and everything works as expected. Users at site C which has a LAN to LAN connection with site A can access shares at site A but not at site B. I appreciate that this is a routing issue but I would be grateful for any advice on how to resolve it.

Thanks

John

If I've understood the topology correctly, it's probably because Site B and Site C do not know that the other one is accessible via the link to Site A. So the traffic is probably heading out of the Default Gateway, en-route to the ISP instead.

There are really only 3 places you can manually add this information :-

• In the "More" section of the VPN definition.


• As a "Routing Policy" entry


• As a Static Route.

(It needs doing at both ends)

Theoretically, this routing information can be discovered by RIP, if enabled.

See: https://www.draytek.com/support/knowledge-base/5765

Thanks for coming back so quickly.

I can see from the route policy diagnostics that you are correct, traffic from site C to site B was being sent out on WAN1. I have created a policy at site C to force traffic to use the VPN when looking for addresses in the site B subnet. The policy diagnostics now shows that traffic is correctly being directed over the VPN but I am still unable to reach anything at site B.

Is there something else I should be doing?

Thanks

I could not get this to work no matter what I did so in the end I just created another LAN to LAN connection from site C to Site B and everything is now working.

I would have replied sooner - but the forum software didn't notify me of your reply

Glad you have it working.

The reason it didn't spring into life with the first Route Policy addition, would have been to do with the Return Path. Traffic from Site C to Site B would have been following the correct Route, but responses from Site B to that traffic would not. (So, for example, if you 'pinged' B from C, it would have gone from C -> A -> B, but when B replied, it would have gone from B -> Default Gateway).

No worries and thanks for coming back to me.

What I have done works but does not feel right.

Could I get this to work by adding additional route policies at site A and at site B to deal with the returns to site C?

Thanks