Sudo certbot certonly --webroot The Certificate Authority failed to download the temporary challenge files created by Certbot

:saluting_face: lease fill out the fields below so we can help you better. Note: you must provide your domain name to get help. Domain names for issued certificates are all made public in Certificate Transparency logs (e.g. |, so withholding your domain name here does not increase secrecy, but only makes it harder for us to provide help.

My domain

I ran this command:sudo certbot certonly --agree-tos --email --webroot -w -d --dry-run

It produced this output:aving debug log to /var/log/letsencrypt/letsencrypt.log
Simulating a certificate request for

Certbot failed to authenticate some domains (authenticator: webroot). The Certificate Authority reported these problems:
Type: connection
Detail: Fetching Timeout during connect (likely firewall problem)

Hint: The Certificate Authority failed to download the temporary challenge files created by Certbot. Ensure that the listed domains serve their content from the provided --webroot-path/-w and that files created there can be downloaded from the internet.

Some challenges have failed.
Ask for help or search for solutions at See the logfile /var/log/letsencrypt/letsencrypt.log or re-run Certbot with -v for more details.

My web server is (include version):ubuntu 22.04

The operating system my web server runs on is (include version): Apache/2.4.52 (Ubuntu)

My hosting provider, if applicable, is:aliyun

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

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

The version of my client is (e.g. output of certbot --version or certbot-auto --version if you're using Certbot):1.21.0-1build1

Welcome @qimiao

Your domain cannot be reached from the public internet using an HTTP request. The HTTP Challenge requires this to work. The most common reason is a firewall is blocking that port.

The Let's Debug test site is helpful while you fix your connection problems. Click its Rerun Test after making changes to confirm fixes.


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