I am new here. I have OpenWrt router configured as access point. I tried installing adblock, but it seems that is not working (blocking ads). I heard some conflicting information whether or not adblock can be run in access point mode. Can you please provide me some further information how to (if possible) configure adblock on my router?
An AP is normally just a plain and dumb media converter between ethernet and WiFi, it doesn't do firewalling, DHCP or DNS services.
Technically you could run adblock on an AP, but in order to have any effect, your main router's DHCP lease would have to divert DNS queries to said AP. In other words, you'd need a main router that is flexible enough to allow configuring that - at which point it doesn't make that much sense to outsource it to the AP (there are a couple of technical caveats, but it's possible - it just doesn't make too much sense).
What setting on main router would allow me to do that?
An alternative way is to intercept DNS queries with AP firewall.
Set up bridge firewall if there's no WAN on AP.
I cannot set DHCP Option 6 on my main router.
So if I understand correctly I only write commands from intercept DNS and bridge firewall links and adblock should work? Or is there other things I need to do / check / be aware of?