My web server is: Apache/2.4.52 (Ubuntu).
The operating system my web server is running on is Ubuntu 20.04.
I am configuring this for the Zammad app.
The zammad.conf in sites-available looks like this
I had this problem just yesterday. I used letsdebug.com website to check my website, and it shows exactly what is returning from their queries to your web server. In my case, it was cloudflare intercepting it and taking them to the "Verify You Are Human" webpage. This caused the challenge to fail. My solution was to disable cloudflare long enough to renew my certs.
The '404' means your Apache returned a 404 (Not Found) to the Let's Encrypt authorization server. The --apache option should have setup your Apache to return the correct value. But, it did not in this case.
I am confident the reason is that your VirtualHost does not have a ServerName for dpm-ticket.chichchoe.com.vn. It only has a ServerName for your local IP. Because of this Certbot could not properly configure your Apache for the challenge.
If adding a ServerAlias to that VirtualHost for your domain name does not help let us know. There are other possibilities but they are less likely. In your case Cloudflare is not involved so that cannot possibly be the solution for you
Was that the entire output? Because an Apache server replies on port 443. Do you have multiple Apache servers? Or just multiple VirtualHosts?
An https request to your dpm-ticket subdomain uses a cert for your dpm-asset subdomain. There must be more involved than you are showing. Would you please explain more?
Is your dpm-asset subdomain handled by this same Apache? How did you get its certificate?
The issue might be as you mentioned. I have two VMware instances running different services: Snipe-IT and Zammad.
VMware 1: Installed Snipe-IT with Apache server, domain name dpm-asset.chichchoe.com.vn. I obtained the SSL certificate using the command: certbot --apache -d dpm-asset.chichchoe.com.vn, and it is working fine.
VMware 2: Installed Zammad with Apache server, domain name dpm-ticket.chichchoe.com.vn. I obtained the SSL certificate using the command: certbot --apache -d dpm-asset.chichchoe.com.vn, and it is currently not working.
Did you mean to type certbot --apache -d dpm-ticket.chichchoe.com.vn ? Because that is what you had in your first post.
More important, how do you ensure requests from the public internet to dpm-ticket get to the correct VM? You should setup an access log for your dpm-ticket Apache and make sure HTTP requests arrive there.
