Overall, although I identified the MTU being the issue on my setup, it leaves me with a conundrum. At 1500 (default) my VPNs work, but due to packet fragmentation RDP to a server i use all the time...

@MR.S Do you get the same effect as i was - VPN connects, devices pingable, but zero TCP/UDP traffic to and from them?

@MR.S Thanks, that is interesting! I havent got around to doing the same test on my spare 605 here, i can try is both as front end to my modem, and behind the ER8411 and see what happens with...

@kogan 1.3.6 showed up in controller as RC once i applied 1.3.5

I have finished my testing, rebuilding everything from scratch, and made the discovery of what is breaking VPNs, on my system at least Things i did, in sequence Factory reset Gateway, Switch, EAP...

@rlp122 Does your ISP connection need a VLAN tag? some do