Hostnames don't resolve behind some routers

[mattshepherd]

Hi,

So i've been connecting to an OpenVPN server hosted on AWS for a few years without an issue whilst at home. However, when trying to connect for certain coffee shops and even friends houses, whilst I can connect, and access resources by IP, I cannot resolve any host names for servers in the VPC behind the VPN.

This recently became a serious issue when i upgraded my home router from a Apple AirPort Extreme to a Ubiquiti Amplifi HD. The Amplifi seems to have the same problems I have had on other networks. I confirmed it was the router but switching back to the AirPort which again, works as expected.

Have tried connecting from a Windows client and macOS client, also from iOS... all work fine on AirPort, not on the Amplifi router.

Any ideas?
Thanks,

Matt