Multi WAN with 1 WAN and LAN through single Long Range Wifi

Here is my issue.
I have two buldings linked by a long range wifi (LR_WiFi). I get about 600mbps. Consider it a cable link.

Currently building 1(my flat) has a slow internet connection which goes through my firewall and then onto the Lan which also gets sent down the LR_WiFi so computers etc in the other building (my workshops have internet and access to my servers.

I am hopefully getting FTTP installed to building 2. But I don't want to stop my internet connection to Building 1, and this may later get FTTP. I have enough use to warrent this and the redundancy is useful to.

Instead I would like to have a multi-WAN setup where the openwrt box uses the best network connection or if one fails the other should stay up.

  1. Is there a way I can sent the building 2 through say a VLAN to appear at the WAN2 port on the openWRT box?
    1.a.Can this all be done in openWRT or would I need to use managed switches for the VLAN through the long range Wifi? to combine and seperate them at each end?

  2. Also it seems odd sending the internet back and forth from building 2. I was wondering if I had 2 openWRT boxes, if I could somehow manage it that way?
    So each box knows there is an alternative gateway (WAN) and can use it if its local WAN is running slowly?
    Ideally I would keep the LANs in both buildings on the same subnet so they can all easily see each other.

  3. I can manage DHCP by either turning assignment off on one box or simply only allowing each to assign a certain range. I think turning it off on one box is safest?

The main question is (2) if I can use 2 openWRT boxes on the same LAN both with incoming WAN and they know that there is an alternative WAN if its local one is running to slow or has failed.

Thanks for your help!

It is better to have 1 router per lan, otherwise it won't be easy to control which one will act as gateway for the hosts.
Use mwan3 for the multiple wans.
Vlans would be a more clean solution, however you can manage to have the second wan over lan with macvlan.

1 Like

Would this mean at the gateway end the openWRT box can deal with the spliting of the VLAN over th e Long range wifi and use one as the second WAN feed. Or do I need a seperate managed switch for this?

If the LANs were seperate with their own gateway, could I still make sure all devices on each LAN could see each other passing things lke bonjour and other stuff that Goggle use to detect devices?
Would they then of course be able to us the other LAN as another WAN access to load balance?

Thanks for tour help.

It depends on the device running OpenWrt on building 1.

Some people have done it. Search for smcroute.