First of all I really like the ease of use of the Rancher loadbalancer for simple tasks.
But there is one thing that keeps me puzzled, after I upgrade a webserver that is behind a loadbalancer I sometimes get 503 notice from the loadbalancer after the webserver is upgraded and running.
Is the loadbalancer doing some health check on the linked containers?
P.S. any tips on how to get zero downtime upgrades would be awesome!