Why did all of my backend Droplets become unhealthy when I enabled PROXY protocol on my load balancer?

If you enable PROXY protocol on a load balancer but the services on the backend Droplets aren’t configured to accept PROXY protocol headers, those Droplets gives a 400 response to the load balancer’s health checks. This means the load balancer considers them unhealthy and stops routing traffic to them.

How you enable PROXY protocol support on your Droplets depends on the software you’re running. Here are some resources for common services:

Kubernetes service ’externaltrafficpolicy’ field controls how nodes respond to health checks.
Load balancers return 503 errors when there are either no Droplets assigned to them or all of the assigned Droplets are unhealthy.