The ‘Unable to Resolve Host’ error can be an annoying but solvable issue for web servers installed on Debian systems. When this error crops up, it is usually related to the machine instances’ ability to communicate with one another, which is especially critical for web servers. In this blog post, we will cover the causes of this error and how to set up a DNS alias to resolve it.
What Causes the ‘Unable to Resolve Host’ Error?
The ‘Unable to Resolve Host’ error usually appears when a server is unable to communicate with an external resource, usually related to your domain name. This can be due to several causes. These include:
- The domain name’s DNS entries aren’t configured correctly.
- The firewall is blocking incoming connections.
- A proxy is interfering with the connection.
- The DNS servers can’t be reached.
- The network cable linking the server is loose or unplugged.
What is a DNS Alias?
A DNS alias is an entry that usually a company will create that points to another domain name or IP address. Usually, a DNS alias is created in order to point users to certain websites. For example, if your company owns the domain www.example.com, you can create a DNS alias like www.example.net to point users to the same resources. This way, users can easily remember the domain name and visit the correct web site.
How to Set Up a DNS Alias on a Debian System
In order to fix the ‘Unable to Resolve Host’ error on a Debian system, you need to set up a DNS alias. To do this, follow these steps:
- Log in to your domain name’s control panel and go to the DNS section.
- Create a new ‘A’ record for the domain you want to use as an alias.
- Set the ‘Type’ field to ‘A’ and the ‘Host’ field to the domain you want to use as an alias.
- Create ‘CNAME’ record for the domain you want to use as an alias.
- Set the ‘Type’ field to ‘CNAME’ and the ‘Host’ field to the domain you want to use as an alias.
- Set the ‘Value’ field to the IP address of the web server.
- Save the changes.
Once you save the changes, the DNS alias should start functioning. Now, users should be able to access the web server by using either the domain name or the alias.
Conclusion
The ‘Unable to Resolve Host’ error can be a pesky issue on Debian systems, but fortunately, it can be solved by setting up a DNS alias. Setting up a DNS alias involves creating two records in the domain name’s control panel, an ‘A’ record and a ‘CNAME’ record. Once the records are created, users should be able to access the web server from the domain name and the alias.
