Webmin is a web-based administration tool for Unix systems.

Also, it provides a feature to create subdomain very quickly.

But, errors such as “Unable to determine IP address from host name xxxx.domain.com” may occur due to the improper settings in the Apache configuration file.

At Bobcares, we often get requests from our customers to resolve the problems with “Webmin Subdomain” as part of our Server Management Services.

Today, we’ll see how our Support Engineers solved the errors related to “Webmin Subdomain”.

How we created Subdomain with Webmin

Unlike cPanel, in Virtualmin/Webmin, there is no direct option for creating subdomains.

In addition, subdomain has its document root inside the parent’s domain document root, as in cPanel. So it’s tricky to create subdomains in Webmin.

For example, the document root of subdomain is  “/home/username/public_html/foldername”.

Let’s see how our Support Engineers set up a subdomain in Webmin.

Steps To Create Sub Domain in Webmin

1. Firstly, we log into Webmin control panel.

2. Then go to Servers > Apache Webserver.

3. From that page, we select “create new virtual host”.

Also, we fill the following field too.

1. Handle connections to address: We select the specific address and IP address of the subdomain in the text field.
2. Document Root: We enter the path of sub-domain,

4. At last, we click on the “Create Now” button.

Now, the subdomain successfully created in Webmin.

Note: once we have created the Webmin subdomain, a proper DNS record must be added to the corresponding subdomain. Otherwise, errors will appear on the website.

However, you may get errors like “Unable to determine IP address from host name xxxx.domain.com” after creating subdomain due to improper settings in the configuration file.

How we fixed Webmin subdomain-related errors

Let’s see how our Support Engineers fixed subdomain-related errors in Webmin.

1. Missing DNS records

Recently, one of our customers came up with a website issue. His subdomain was not working and showed an error as “Unable to determine IP address from host name test.domain.com”.

Then our Support Engineers took the following steps to solve the issue.

1. First, we used the “dig” command to verify that the subdomain name is resolved to the correct IP address.

2. Then we found that the subdomain didn’t have an “A record”.

3. So, we added the “A record” via Webmin. We go to Servers > BIND DNS Server.

4. Next, we selected the zone of the parent domain and clicked on “Add Record To Selected” button.

Also, we added the following fields too.

1. In new Record Name field, we entered the subdomain name.
2. In new record field, we entered the IP address.

5. Finally, we clicked on the Add Record button.

That’s fixed the problem.

2. Wrong settings in the Apache configuration file

Similarly, another customer had an issue with subdomain creation. He failed to create subdomain through Webmin.

So, our Support Engineers analyzed the error log in Apache server and found a misconfiguration in httpd.conf.

Furthermore, we checked the configuration file and made corrections in /etc/httpd/conf/httpd.conf file.

We corrected the ServerName and ServerAlias and restarted Apache to apply the configuration changes.

ServerName www.subdomain.xxxx.com
ServerAlias subdomain.xxxx.com

This is how we fixed the problem.

[Getting errors while creating subdomains in Webmin? We’ll fix it for you.]

Conclusion

In short, customers may fail to create Webmin subdomain due to improper settings in the Apache configuration file or because of missing DNS record. Today, we saw how our Support Engineers configured subdomain in Webmin and fixed Webmin subdomain-related errors.