On: I can see your local web servers

[OvermindDL1]

Wait, doesn't the certbot DNS challenge query the nameservers of the domain being checked, not your local DNS resolver, otherwise my fast DNS challenges should fail?

[lostjohnny → OvermindDL1]

Not by default [1], but you can set it to what you prefer.

But in my case my network is configured to always reach the in house DNS first, to keep latency low

[1] https://github.com/letsencrypt/boulder/blob/8167abd5e3c7a142...