What is DNS-based load balancing?
DNS load balancing is a method of distributing client requests across multiple servers by configuring a domain in the DNS, enhancing performance and reliability. 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 example, 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.
See also: DNS server, load balancer, Round Robin DNS, DNS failover, DNS round-robin
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. For example, if server A goes down, traffic switches to server B.
- Weighted round-robin: Allows you to distribute uneven amounts of traffic across multiple servers. For example, server A gets 70% of traffic, server B gets 30%.
- Round robin: Allows you to distribute traffic equally between your servers and redundant internet connections. For example, server A gets the first request, server B the second, and so on.
- Latency routing: Uses health checks to decide which server (or other resources) can handle your web traffic best. For example, traffic is sent to the server closest to the user for faster response.
