Asus OpenVpn Server behind behind another router (Google Mesh).

[MonkeyB]

Hello everyone,

I currently have a OpenVPN server (at a friends home) running properly on a Asus Router. He uses a Google Home mesh as his router.

Currently the connection is: ISP Modem -> Asus Router -> Google Home.

He has recently started to complain that once a day his internet drops for a few minutes before starting back up. Due to this, I want to change the connection configuration to ISP Modem -> Google Home -> Asus Router for VPN Server.

All I want to gain is the IP address/Internet Access. I do not need access to local devices or anything else.

I hear a lot about double NAT and stuff but is it impossible to have my configuration setup like this?

Will assigning a Static IP (DHCP IP reservation) to the Asus Router and forwarding necessary port do the trick? Or is there anything else I need to be looking at.

I currently do not have access to the router setup and I would be traveling to set it up over the weekend. Your suggestions will be greatly helpful and would save me a lot of effort.

Thanks

 

[eibgrad]

I don't see any obvious problem w/ the OpenVPN server being behind the Google Home router anymore than if it was on a server or any other device behind the Google Home router. It just happens to be a router.

The double NAT situation can be problematic for other reasons though. For example, suppose the ASUS router is supporting PnP (Plug and Play) for an XBOX. Well now the XBOX is managing ports on the *internal* router, NOT the one w/ the public IP! While it may be able to manage ports on the ASUS router, that will NOT propagate to the primary router (Google Home). You may want to place the WAN ip of the ASUS router in the DMZ of the Google Home router so all unsolicited inbound traffic to the public IP that is NOT intended for the Google Home private network is automatically passed to the ASUS router.

Other systems may have problems w/ double NAT as well (e.g., VOIP).

So I don't think the OpenVPN server itself is the issue. It's whether the double NAT causes *other* issues you may not already be considering or know about.