[Cloudflare] Web server is down - Error code 521

| SYSTEM INFORMATION |
|------------------------------|-------------------------------|
| OS type and version | Windows 11 Home - Version 22H2 |
| Webmin version | 2.001 |
| Virtualmin version | 7.2-1 |
| Related packages | SUGGESTED |

Hello everyone,

I receive the message in the subject line once connecting to the domain of the “Server1” from all browsers, Chrome and Firefox. Until yesterday everything was running smooth for “Server1”.

The only action taken yesterday was cloning from “Server1” another “Server2”. The procedure finished in a failure because for the “Server2” I received instantly a Forbidden 301 message. So, yesterday night I deleted “Server2” in order to restart again the procedure today after about 8 hours of “pause”…

Result? Both of them are now under Error code 521.

Did I miss something? How can I solve in your opinion?

Thank you in advance.

My best regards.

This means that your web-server (like Apache or Nginx) is not running.

1 Like

Thank you Ilia, on the attachment basis, how do you please suggest it is better to proceed?

The error is self explanatory. You should fix the path to the SSL certificate file for the given virtual server.

Perhaps, the work-around would be as simple as to toggle SSL website feature using Edit Virtual Server page.

1 Like

Hi Ilia

I tried to uninstall and then install SSL certificate as you suggested and I received the following:

Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator webroot, Installer None
Obtaining a new certificate
Performing the following challenges:
http-01 challenge for admin.lemigliorioccasioni.com
http-01 challenge for mail.lemigliorioccasioni.com
http-01 challenge for webmail.lemigliorioccasioni.com
Using the webroot path /home/lemigliorioccasioni/public_html for all unmatched domains.
Waiting for verification...
Challenge failed for domain admin.lemigliorioccasioni.com
Challenge failed for domain mail.lemigliorioccasioni.com
Challenge failed for domain webmail.lemigliorioccasioni.com
http-01 challenge for admin.lemigliorioccasioni.com
http-01 challenge for mail.lemigliorioccasioni.com
http-01 challenge for webmail.lemigliorioccasioni.com
Cleaning up challenges
Some challenges have failed.
IMPORTANT NOTES:
 - The following errors were reported by the server:

   Domain: admin.lemigliorioccasioni.com
   Type:   dns
   Detail: DNS problem: NXDOMAIN looking up A for
   admin.lemigliorioccasioni.com - check that a DNS record exists for
   this domain; DNS problem: NXDOMAIN looking up AAAA for
   admin.lemigliorioccasioni.com - check that a DNS record exists for
   this domain

   Domain: mail.lemigliorioccasioni.com
   Type:   dns
   Detail: DNS problem: NXDOMAIN looking up A for
   mail.lemigliorioccasioni.com - check that a DNS record exists for
   this domain; DNS problem: NXDOMAIN looking up AAAA for
   mail.lemigliorioccasioni.com - check that a DNS record exists for
   this domain

   Domain: webmail.lemigliorioccasioni.com
   Type:   dns
   Detail: DNS problem: NXDOMAIN looking up A for
   webmail.lemigliorioccasioni.com - check that a DNS record exists
   for this domain; DNS problem: NXDOMAIN looking up AAAA for
   webmail.lemigliorioccasioni.com - check that a DNS record exists
   for this domain


Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator manual, Installer None
Obtaining a new certificate
Performing the following challenges:
dns-01 challenge for admin.lemigliorioccasioni.com
dns-01 challenge for mail.lemigliorioccasioni.com
dns-01 challenge for webmail.lemigliorioccasioni.com
Running manual-auth-hook command: /etc/webmin/webmin/letsencrypt-dns.pl
Running manual-auth-hook command: /etc/webmin/webmin/letsencrypt-dns.pl
Running manual-auth-hook command: /etc/webmin/webmin/letsencrypt-dns.pl
Waiting for verification...
Challenge failed for domain admin.lemigliorioccasioni.com
Challenge failed for domain mail.lemigliorioccasioni.com
Challenge failed for domain webmail.lemigliorioccasioni.com
dns-01 challenge for admin.lemigliorioccasioni.com
dns-01 challenge for mail.lemigliorioccasioni.com
dns-01 challenge for webmail.lemigliorioccasioni.com
Cleaning up challenges
Running manual-cleanup-hook command: /etc/webmin/webmin/letsencrypt-cleanup.pl
Running manual-cleanup-hook command: /etc/webmin/webmin/letsencrypt-cleanup.pl
Running manual-cleanup-hook command: /etc/webmin/webmin/letsencrypt-cleanup.pl
Some challenges have failed.
IMPORTANT NOTES:
 - The following errors were reported by the server:

   Domain: admin.lemigliorioccasioni.com
   Type:   dns
   Detail: DNS problem: NXDOMAIN looking up TXT for
   _acme-challenge.admin.lemigliorioccasioni.com - check that a DNS
   record exists for this domain

   Domain: mail.lemigliorioccasioni.com
   Type:   dns
   Detail: DNS problem: NXDOMAIN looking up TXT for
   _acme-challenge.mail.lemigliorioccasioni.com - check that a DNS
   record exists for this domain

   Domain: webmail.lemigliorioccasioni.com
   Type:   dns
   Detail: DNS problem: NXDOMAIN looking up TXT for
   _acme-challenge.webmail.lemigliorioccasioni.com - check that a DNS
   record exists for this domain

so I registered the A and AAAA (not the TXT) records.

Did I apply the correct procedure?
How did that malfunction occur in your opinion?
If I create a new virtual server by cloning that one, will I face the same problem?

For the time being, now Apache is running properly, thank you very much for your kind assistance.