I wanted to have an HA forward proxy solution using Squid, and I am trying to use the Squid servers behind ELB solution on page 41.
However, my forward proxy service is a service meant to forwarding traffic to an internal network (back to my corp network), i.e., there is no Internet connection for my Squid servers. Therefore, health check about a well-know URL such as google.com does not work.
With the solution describe on page 41 above what is the best way for ELB to do health checking toward the Squids servers? Which ping path I should be using in this scenario?
An ALB health check can be changed to expect a non-200 http status code response from the target. You can go to the squid root path on say port 3128 and expect a 400. In the AWS console, go to the TargetGroups, find your group, select the Health checks and change the Success codes to 400. Set the Path attribute to /.