In 2023, online businesses and applications should use canonical name (CNAME) DNS records for several reasons, including flexibility, redundancy and load balancing. CNAME records are ideal for simplifying DNS record management for a domain: instead of having to update multiple A records whenever an IP address changes, you can easily update a single CNAME record and point to a new domain. This is particularly useful for businesses that frequently change their web hosting or CDN providers. CNAME records also play a huge role in creating redundancies for critical services. It can use a CNAME record to point to a primary server and a secondary CNAME record to point to a backup server. In the event of the primary server being down, traffic is automatically redirected to the backup server.

What is a CNAME record?

A CNAME record is a type of DNS resource record that maps one domain name to another. CNAME records allow you to create an alias for a domain name, such that when a client performs a lookup for the alias, it will retrieve the actual address (or "canonical" name) associated with the target domain.

CNAME in the real world

CNAME records are commonly used when a provider requires a specific hostname to be used for a service, or when a user wants to create a user-friendly domain name that redirects to a longer or more complicated address. It is important to note that a CNAME record can only be used to map one domain name to another and cannot be used to redirect the root of a domain to another address.

In the instance you have a website running on the domain www.example.com, you could create a CNAME record that maps the domain alias.example.com to www.example.com. When a client performs a lookup for alias.example.com, it will receive the address of www.example.com as the result and will be able to access the website by visiting that address.

Common use case for CNAME records

CNAME redirects
CNAME records can be used to redirect multiple domain names to a single website, allowing organizations to have multiple points of entry to their website while still only having to manage one domain. This can be useful in cases where a domain name has changed, but existing links and bookmarks need to be redirected to the new domain.

Round robin weighted CNAME
A common load balancing technique is round robin, which is used to balance traffic across multiple servers. While basic round robin is restricted to even distribution, weighted round robin can be dispersed among servers unevenly. With DigiCert Constellix DNS, this can be achieved by utilizing DNS record pools.

Load balancing
Utilizing CNAME records can be used to distribute traffic across multiple servers to balance the load and ensure high availability. For example, a business could use a CNAME record to distribute traffic between several web servers or CDN nodes, based on factors such as geographic location or server load.

Domain aliasing
CNAME records are often used to alias one domain name to another, making it easier for users to remember the domain name and access the website. CNAME records can be used to create a domain alias, where a secondary domain name points to a primary domain name.

Third-party services integration
Use CNAME records to integrate third-party services into a website, such as social media widgets, analytics tools and content delivery networks (CDN).

Subdomains
CNAME records can be used to create subdomains. This allows organizations to have multiple websites within a single domain, each with its own unique URL. This tool can be useful for different services or applications such as a blog, store or online forum.

Email hosting services
CNAME records can be used to host email services on a third-party provider, allowing organizations to use the email services without having to manage their own email servers.

Multi-CDN using CNAME
Multi-CDN involves using multiple content delivery networks to distribute content, which can improve website performance, reliability and availability. By using CNAMEs, you can direct traffic to the most optimal CDN based on various factors such as the user's location, CDN availability and content type.

For example, you can set up a CNAME record that maps your domain name to multiple CDN providers. When a user requests content from your website, their DNS resolver will resolve the CNAME record and direct the request to the most optimal CDN based on the user's location and other factors.

Using CNAMEs can also simplify the management of multiple CDN providers. Rather than managing each CDN provider individually, you can manage them all through a single DNS record.

CDN integration
Integrate content delivery networks into a website with CNAME. This gives organizations the opportunity to optimize the delivery of their content to users around the world. CNAME records can be used to route traffic to a CDN for optimized website delivery. The CDN is assigned a CNAME record, which routes the traffic to the nearest available server.

Smart branding with CNAME 
CNAME records can be used to create branded subdomains for various products or services, giving each a unique presence while still being hosted on the same domain.

Latency-based CNAME

Latency-based CNAME resolution is a technique used to improve the performance of a website or application hosting by directing requests to the closest available server. This creates the ultimate speed scenario. And we know faster resolutions yield a low bounce rate and a high ROI.

In a traditional DNS setup, a CNAME record is used to alias one domain name to another. When a user types in a domain name, their DNS resolver looks up the IP address associated with the domain's DNS record and directs the user to the corresponding server.

In a latency-based CNAME resolution, however, the DNS record is dynamically updated to point to the server that is geographically closest to the user. This is accomplished by using DNS queries that test the response time of different servers and choose the one with the lowest latency.

This approach allows for faster load times and improved user experience, particularly for users who are far away from the hosting server. Latency-based CNAME resolution is commonly used by content delivery networks (CDNs) and other large-scale hosting providers to improve the performance of their services.

CNAME and the user experience

There’s no doubt that using CNAME records can benefit your domains by allowing you to improve their functionality, enhance their branding and boost their SEO. Whether you need to set up a custom domain for your landing pages, create subdomains for your web apps or consolidate your domain names for better management, CNAME is a versatile tool that can help you achieve your goals. By leveraging the power of CNAME, you can streamline your online presence, increase your visibility and provide an ideal user experience for your visitors.

Reach out to one of our expert team members to see how DigiCert DNS can customize a DNS plan that is the ideal fit for your organization.