Using OpenWrt as WAP(s) behind a Starlink Gen 2 router

Installing and Using OpenWrt Network and Wireless Configuration
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I moved to OpenWrt when I started beta testing for Starlink. For my own use on Gen 1 and now on Gen 2 I just run the Starlink router in bypass mode and use the ethernet adapter to run a pfSense appliance with 5 OpenWrt WAPs on backhaul on my property to deliver multiple VLANs and WiFi instances.

A neighbor is gearing up to move his home to Starlink but has been running his single SuddenStop router/wifi out of his garage so he can get internet (wifi only) to his shop 75ft away. So he's always had sketchy wifi in his home and his shop.

I'd like to run his Starlink router in his home with the ethernet adapter to a small switch and run an OpenWrt instance (or 2) as a WAP with backhaul using one of the IP addresses on the Starlink Gen 2 router that are outside the DHCP pool. Those addresses are supposedly in the .2 to .19 range on a 192.168.1.0/24 network.

Is anyone else running with this sort of setup? Can you confirm the use of .2 to say .4 IPs as being usable outside the pool range? Any setup tricks to know on building the WAP or maybe two for him behind the Starlink router? I'm well versed in getting OpenWrt configured as a WAP but am curious if there are any gotchas or gimmes when operating behind the Starlink router.

Thanks,
Rick

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Starlink has a guidance on how to use 3rd party router (replace small switch with big openwrt router) and make theirs into the "bypass mode".

We dont manage your starlink dhcp, no telling how it assigns IPs. You need to exactlly observe its IP assignmets and guess the next one.

Guide on adding "dumb" access points

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Bridged APs are very little more than media converters between wired and wireless. They don't alter or make decisions on the packets between the main router and wifi users. All routing, firewalling, DHCP, and DNS is passed through to the main router.

The only reason an AP holds an IP address at all is so the OS can be reached for administrative purposes, and it can reach the Internet for internal use like NTP and software upgrades. Users of the AP never send anything to or from that address. The AP will keep working even if it is statically set to an unworkable IP (outside the lan subnet). To avoid that if the main router changes, I usually set up APs as DHCP clients.
If necessary to ssh to one, log into the main router and find its IP address in the lease table.

Consider (with permission) installing Zerotier or Tailscale on the APs so you can reach them remotely by their VPN address regardless of LAN IP. This also works from inside the same network.

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If the goal is to maintain LAN access behind remote Starlink CGNAT Routers, then consider using Tailscale.

Tailscale can be installed on your pfSense Router and on your neighbours OpenWRT Router.

Tailscale allows each party to establish and administer their own Tailnet and grant access to selected devices.

5

Have you ever captured/parsed your Debug Log? Lots of info to be gleaned.

cat <debug log filename>|grep -n -A 9 networks

Should return something like this:

769:          "networks": [
770-            {
771-              "ipv4": "192.168.1.1/24",
772-              "dhcpv4Start": 20,
773-              "dhcpv4End": 254,
774-              "dhcpDisabled": false,
775-              "dhcpv4LeaseDurationS": 3600,
776-              "domain": "lan",
777-              "basicServiceSets": [
778-                {
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Thanks, but I'm not trying to do a third party, I do that at home and was brought in on the beta for that reason. For my neighbor I WANT to use the Starlink Router. I was just hoping someone had some experience running OpenWrt (dumb) WAPs behind the Starlink Gen2 router.

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Yep, and thanks. Unfortunately, Starlink doesn't permit the modification of their routers other than turning a (very) few features on or off. You can run it in bypass and use your own router or use their locked down config. For my neighbor, he is an awesome machinist but hasn't a clue on his internet connectivity so I'm hoping to get him on a "set and forget" setup.

8

Fastest router connetced to starlink and does nat and dhcp. That way you can set DHCP handouts as you wish.

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Yes, I have done this numerous times.
To modify a famous quote - "the best ipV4 config is no ipV4 config". Then you do not have to worry about it. There is no guarantee a future Starlink upgrade won't change the dhcp pool range.

Configure your WAPs to use dhcp. Then if you, or anyone else for that matter, want to do maintenance or admin work, just use the Starlink app to look up the ipv4 addresses.
This is found under "Network". Select the required hostname to get the ipv4 address.

Remember to add a memorable hostname in /etc/config/system and it is done.

Sooo simple and pain free :man_tipping_hand:

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