I have 2 OpenWRT devices. One is on 19.07.4 and is connected to the internet. The other was originally on lede 17.01 and was serving as a dumb ap and this seemed to work. I've now upgraded the Dumb AP to 19.07.4, and when devices connect to the dumb ap they seem to only get allocated a link-local ip6 address and no ipv4 address (which ought to come from the dhcp server on the main, internet-connected openwrt instance).
Any idea where I should look?
Post your configs redacting the private parts:
uci show network; uci show wireless; uci show dhcp; uci show firewall; \
head -v -n -0 /etc/resolv.* /tmp/resolv.* /tmp/resolv.*/*; \
ip address show; ip route show; ip rule show; iptables-save
When you upgrade from 17 to 19 (or any other major version) you should not keep the configuration between upgrades.
Even if everything looks fine in the configurations @vgaetera requested, I'd suggest to reset to defaults and follow the dumbAP guide from scratch.
Ok I did keep my config files while upgrading, I'll reset to defaults and see if that sorts it out. Thanks.