I recently flashed the current OpenWRT (18.06.2 ) on a GL-AR150, and it's my first try of the "real" OpenWRT (apart from all kinds of Freifunk routers I'm taking care of).
Unfortunately, I ran into a – for my use case – severe problem/bug I reported at https://bugs.openwrt.org/index.php?do=details&task_id=2145 : no IPv4 DHCP addresses are offered if no LAN cable is plugged when the device boots (cf. the bug report).
I'm pretty sure this is an issue that should (and will) be fixed, but my problem is that – at the moment – I simply can't use the device at all, because I do need IPv4 addresses and the router is intended to be booted without a LAN cable attached.
I don't want to reflash the original firmware if I can avoid it, so here's my question: Can anybody tell me how to fix this for now, until a release fixing this issue will hopefully be done?
Thanks for all help in advance!
Here's the quintessenece of the longish discussion below:
Apparently, this is an issue caused by the dnsmasq init script doing unneccessary checks that fail and prevent the dhcp range to be added to the dnsmasq config, which then results in dnsmasq not offering dhcpv4 addresses.
The simplest workaround is to set the "force" option to the "lan" section of /etc/config/dhcp. This one is also confirmed to be used by the original firmware used by GL.iNet. (as posted by vgaetera at [Workaround] GL-AR150: No DHCP if LAN cable is not plugged during boot ).