Domain Name System (DNS) records are the backbone of internet navigation. They are what make it possible for domain names to point you to specific web servers, email servers, or cloud services. But what about subdomains? 

Subdomains are critical for organizing your services and scaling web applications. Often referred to as hostnames, configuring these DNS records correctly ensures that your services remain accessible, fast, and secure. 

In the following guide, we’ll break down everything you need to know about how to configure DNS records for subdomains. 

What Are Subdomain DNS Records?

A subdomain is a prefix that exists under a main domain name. For example, in “support.example.com,” support is the subdomain of example.com. Subdomains help organize and route traffic to specific services, such as support portals and developer APIs. On No-IP you will more often see the name hostname used interchangeably with subdomain.

Subdomain DNS records tell the internet where to send users when they visit those addresses. Without the right records, traffic will get lost in the shuffle. DNS queries may fail, resulting in errors or routing to the wrong place. 

Subdomains can be easy to overlook, but  behind the scenes all of the internet relies on precisely configured subdomains or hostnames. For example, cdn.noip.com and dynupdate.no-ip.com drive the relevant internet traffic to different locations and are critical subdomain DNS records, even though they are not something a user would go to naturally. 

Step-by-Step Guide to Configuring DNS Records for Subdomains

There are many different ways to create and configure subdomain DNS records. The trick is to find a simple, easy-to-manage approach. One of the best ways is to use No-IP, a managed DNS and dynamic DNS solutions provider. 

Here’s how to configure DNS records for subdomains with No-IP:

Step 1: Create a Subdomain

Creating a subdomain is simple with No-IP: All you need to do is follow these steps:

• Log in to your No-IP account 
• Navigate to your DNS records page
• Click on  “Add a Hostname” 
• Enter your desired subdomain (hostname) name
• Choose the DNS record type and continue to setup

No-IP allows you to create  hostnames and subdomains easily. Our free dynamic DNS service is one convenient option, though you can also use a custom domain that’s registered elsewhere.

Step 2: Choose the Right DNS Record Type

Selecting the correct DNS record depends on the kind of service the subdomain will point to. Here’s a quick breakdown of the most relevant types:

• Address (A) Record: Points a subdomain or hostname to an IPv4 address; the most used  choice for self-hosted services or servers 
• Canonical Name (CNAME) Record: Points a subdomain to another domain name; useful for directing traffic or connecting your domain to services like GitHub
• Mail Exchange (MX) Record: Directs email traffic to a mail server; needed for domains  that handle email 
• Text (TXT) Record: Used to store text information that is typically used for verification

Knowing the purpose of each record type ensures that traffic is routed correctly and that your services run smoothly. On the other hand, improper routing can lead users to “dead ends,” which are undeniably frustrating.

Step 3: Create  the DNS Record

Once you’ve selected the type of record, you’ll need to input the records’  details. At a minimum, you will need to provide the following information:

• Hostname: Your subdomain (i.e., “vpn.example.com”)
• Record Type: One of the above record types that applies to your intended use case 
• Target: The destination, such as an IP address (for A records), another domain (for CNAMEs), or a mail server (for MX records)

After entering the necessary information, save your record. No-IP’s dashboard makes the process quick and easy, and the record should be active immediately. No-IP makes adding new hostnames effortless, even if you are a true beginner.

Step 4: Verify DNS Configuration

You cannot simply assume that everything is live after entering your DNS record information; you need to verify that your services  are working correctly. And in order to do that, you can do the following:

• Use a website like whatsmydns.net or dnschecker.org to check if the hostname or DNS record is resolving
• Use command line tools such as dig or nslookup
• Ping the subdomain or try accessing it through your browser

Remember, DNS changes take time to take full effect across global internet servers. Most DNS records will propagate across all web servers within a few minutes, though some DNS records (like NS records)  can take up to 48 hours.

Issues & Troubleshooting Tips

No-IP makes DNS management simple and easy. However, a few issues can still pop up. These issues are not usually related to No-IP, but are instead the result of simple oversights during DNS creation or back-end propagation delays.

Here are a few common issues you may encounter:

• Propagation Delays: New records can take time to reflect across global servers 
• Incorrect Record Values: A single mistype in the IP address or hostname/target can lead to access issues
• Conflicting DNS Records: Make sure you don’t have multiple conflicting records (i.e., A and CNAME for the same subdomain)
• DNS Lookup Errors: Use online tools to identify whether the issue lies in routing or server configuration

When in doubt, No-IP’s support team and robust knowledge base are great places to start resolving these problems. If you can’t track down the information you need in our knowledge base, connect with our support team directly for assistance. We will find and fix the issue in no time.

Why Choose No-IP When You’re Managing Subdomains?

Delivering managed DNS is the top priority for No-IP. Our platform is a trusted provider for millions of users, from hobbyists and gamers to large enterprises. Here’s why managing your subdomains with No-IP is a smart move:

• Reliable management 
• Simplified setup
• Dynamic DNS with  broad integration across thousands of devices
• Extensive support and documentation
• Scalability and security

Power your subdomain with confidence by partnering with No-IP. Sign up for DDNS or managed DNS services today.