I used a travel router at the last hotel I was at but didn’t realize the firmware was buggy — it wouldn’t respond to DNS queries whatsoever on my personal network.
I unfortunately forgot my Ethernet cable so it was a real challenge.
Remembering that iOS uses Wi-Fi Privacy (changes MAC address constantly) I just brought up their portal on my phone, signed in, cloned the MAC address then on iOS chose “Forget this Network.”
Worked like a charm! (Then the travel router updated its firmware and DNS was back on track.)