DNS load balancing
(also DNS-based load balancing)
DNS load balancing definition
DNS load balancing happens when you configure a certain domain in your Domain Name System (DNS) to distribute client requests across a group of servers instead of one. The domain you’re configuring can correspond to a mail system, a website, a print server, and many other services that use the internet to function.
DNS load balancing is useful because it protects organizations from server failure and downtime. It also allows them to handle high traffic volumes. It can do so because with DNS load balancing and assigning one domain to distribute requests to multiple servers, you make your service non-dependent on one server. For instance, let’s assume you have a website. If you practice DNS load balancing on it, you essentially employ multiple servers to handle visitors that want to access the website instead of one. That way, if one server fails, another server will open the website for the visitor, and the visitor won’t even know that one of your servers has failed since your website will still be available online.
DNS load balancing types
- DNS failover: One of the most common DNS load balancing types that allows your domain to be active even if your primary server experiences issues and outages.
- Weighted round-robin: Allows you to distribute uneven amounts of traffic across multiple servers.
- Round robin: Allows you to distribute traffic equally between your servers and redundant internet connections.
- Latency routing: Uses health checks to decide which server (or other resources) can handle your web traffic best.