A proxy is a computer or software system that acts as a dedicated intermediary between an endpoint device and another server.
Proxies are meant to prevent cyber-attacks.
PROXY protocol is a protocol for sending client connection information, such as origin IP addresses and port numbers, to the final backend server, rather than discarding it at the load balancer. This can be helpful when analyzing traffic logs or changing application functionality based on geographical IP.
DigitalOcean Load Balancers support PROXY protocol version 1. You can configure your backend services to accept PROXY protocol headers after you enable it on your load balancer.
Enabling the PROXY protocol allows the load balancer to forward client connection information (such as client IP addresses) to your Droplets. The software running on the Droplets must be properly configured to accept the connection information from the load balancer.
Backend services need to accept PROXY protocol headers or the Droplets fail the load balancer’s health checks.