he said that dns resolution worked after he changed dd-wrt config, but I assume that means not on the android box, but on some other machine on his lan. If its still throwing errors on android (as shown by the log), then some issue with android and his local dns.
I’ve seen similar behaviors between different configured machines on my own local lan where some could resolve things and others could not resole the same things
Well, it seem to be “another” DNS issue. Finally, I have found a workaround. I setup another DNS server on my LAN (pi-hole) and I have setup the DNS provided to my client by DHCP with the IP of my new pi-hole server. Pi-hole is configured to use google DNS server and by this way it’s working. I also setup DNS forwarding for lan domain in the pi-hole server to keep the name resolution in my lan.
If I use my router as DNS, even with DNS Rebinding plex.direct exception it doesn’t work. The option is not present in the WebUI, so I suspect that applying the exception in command line in the router doesn’t mean it can handle this setting.
For your information, my router is an Securifi Almond+ running open-wrt.