Multiple proxy server problem

Hi,

I have multiple proxy-server and on their haproxy load balancer. When I set source to balance option in haproxy.cfg, load balancer is going to only one proxy server. but When I set roundrobin to balance option in haproxy.cfg, load balancer is going to once firstly proxy server then once secondly proxy. When I click on each, horizon show different container. Example, firstly, I click to container, horizon is show x, y, z containers. secondly, I click to container, horizon is show a, b, c containers. and Thirdly,I click to container, horizon is show x, y, z containers.
when we have multiple proxy server, Have each proxy server different container knowledge?

Thanks.