Hi everyone,
I am posting here after struggling for multiple days on getting OpenWrt to work on my Raspberry Pi 3 (B model). Basically, we moved and our usual router (TP-Link WDR3600 running OpenWrt) is gone and I thought this was a great opportunity to run OpenWrt on the Pi as a temporary router in the meantime (I have a serial line available all the time on it).
The Pi sits (as did our router) behind an Arris Surfboard SB6121 DOCSIS 3 cable modem. The cable modem is a blackbox to me but I think it acts as a bridge since the machine connected to it gets a public IP address like 73.15.XX.YYY (same as returned by ipecho dot net).
I flashed openwrt-18.06.2-brcm2708-bcm2710-rpi-3-ext4-factory.img on the device and could successfully start the radio and connect to LuCi over both Ethernet cable and wireless.
The issues started when I tried to move eth from the standard configuration to share Internet access from the cable modem. I tried to do things via LuCI but I would get disconnected when splitting the eth0/wlan0 bridge or assigning eth0 to the WAN zone. The UI would freeze, the timeout would indicate something went wrong and it would try to rollback, leaving the config in a halfway state.
In the end, I could make things work (I am writing this post from my laptop connected to the Pi sharing its Internet connection) by following the instructions from https://forum.openwrt.org/t/single-port-devices-define-wan-port/3344/2 (thank you so much!)
So here are some bulk questions, I hope the information will be useful to others as well (let me know if you want this split into topics):
- Is using LuCI expected to work when doing such a bridge/interface reassignement for single port routers or is the commandline the thing to use here?
- LuCI shows that masquerading is not enabled whereas I read it needs to be enabled (cf various links on the forum, I can only put 2 in my first post) for instance?
- LuCI also shows that WAN is red (not up) whereas it is actually working.
- Is the issue w/ eth0 needing to be under a bridge applies to model B (and not B+), cf https://forum.openwrt.org/t/18-06-on-raspberry-pi-3-b/18670/8 ?
Thank you very much for your help on all this, and let me know how I can improve the docs if needed!
Vincent