Certbot timing out despite port 80 being exposed and able to serve pages

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My domain is: treecycling.diverseabilities.org.uk

I ran this command:
sudo certbot certonly --standalone

It produced this output:
Certbot failed to authenticate some domains (authenticator: standalone). The Certificate Authority reported these problems:
Domain: treecycling.diverseabilities.org.uk
Type: connection
Detail: Fetching http://treecycling.diverseabilities.org.uk/.well-known/acme-challenge/6txu8pJs-1hGmgQbSsz4KBn1GNLkxfPE2iJhpJ5Iyvw: Timeout during connect (likely firewall problem)

My web server is (include version):
A Go web application.

The operating system my web server runs on is (include version):
Ubuntu 21.04 x86_64

My hosting provider, if applicable, is:

I can login to a root shell on my machine (yes or no, or I don't know):

I'm using a control panel to manage my site (no, or provide the name and version of the control panel):

The version of my client is (e.g. output of certbot --version or certbot-auto --version if you're using Certbot):
certbot 1.20.0

I'm also getting a time out on port 80.

Usually, when there's no firewall blocking the port, even when there isn't an application listening on a certain port, a client should get a response from the operating system. Obviously when there is an application listening, that application would respond, but when nothing is listening you'd usually get a "Connection refused" ICMP reply from the server. I'm not getting that. I too am getting a time out.

So please check all possible firewalls, as port 80 doesn't seem to be exposed, possibly only to certain regions of the world.


Hi @thedarkb and welcome to the LE community forum :slight_smile:

I also see what appears to be a firewall drop for HTTP requests.

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How are you seeing this, out of curiosity? I've restarted the server to show that HTTP requests are getting through, it's only LE ones that are having trouble.

Nmap from a remote machine shows the HTTP port as being open.

It fails after about 10 seconds.

curl -Ii http://treecycling.diverseabilities.org.uk/
curl: (56) Recv failure: Connection reset by peer

I reckon this must be an ISP issue because I can connect from my English VPN but not from my own Irish IP address. Sorry about that.


Geolocation policy being applied somewhere?


According to traceroute, it's just getting black holed by one of Vultr's routers, so I have honestly no idea. There is no geolocation policy in force.

The there is some other force at play...
Luke, I am your father!


Luke, you should have :beer: , while I have more :beers:

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