HA proxy load balancer

 good for manual configured proxy, reverse proxy, load balancer

need to configure a front end

then backend to redirect traffic to different nodes

https://www.youtube.com/watch?v=9GWziEBoDqQ&t=328s

https://www.haproxy.org/

https://serverfault.com/questions/788132/how-to-configure-haproxy-as-a-reverse-proxy

frontend localhost
    mode http
    use_backend web1 if { hdr(host) -i abc.com }
    use_backend web1 if { hdr(host) -i def.com }
    use_backend web2 if { hdr(host) -i cba.com }
    use_backend web2 if { hdr(host) -i fed.com }

backend web1
    server web1 web1.foo.com

backend web2
    server web2 web2.foo.com