HAproxy frontend hostnames

I’m using Rancher 1.6.22 with HAproxy 0.9.6 (from image rancher/lb-service-haproxy:v0.9.6) and on HAproxy statistics report page I could see backend with nice names (taken from Backend name), but all containers have some hash instead of hostname:


Is there any way how to set hostnames instead of these hashes? We used to use Docker Cloud also with HAproxy and there were hostnames like: gateway_1, gateway_2, gateway_3 etc.

Thanks a lot!