DNS Load Balancing

### Round-Robin DNS

One of the simplest forms of load balancing occurs at the DNS level. A single domain name is configured with multiple IP addresses (A records). The DNS server returns the list of IPs in a rotating order, distributing traffic evenly.

### Advanced DNS Routing

Modern managed DNS providers (like AWS Route53 or Cloudflare) offer advanced routing capabilities: - **Geolocation Routing:** Directs users to the closest data center based on their geographical location, significantly reducing latency. - **Health Checks:** DNS providers can actively monitor endpoint health and automatically stop returning the IP of a failing server.

While powerful, DNS caching by ISPs can sometimes delay the propagation of health-check-based failovers.