I’m running an Exchange 2013 on-prem environment through HAPROXY (1.8.16) and recently discovered an issue where I have multiple URLs pointing to one VIP on the load balancer (centos7). For example:
all point to 10.1.2.25
As a client, if I navigate to email.cloud.domain.com - haproxy initially sees my request but somewhere it gets re-written to email.domain.com. This only happens when a client is talking directly to the haproxy lb IP. Externally the traffic goes via a firewall and this behavior does not occur. What configuration could be causing this?
Additional info: I originally thought this was only happening for similar DNS entries into one VIP, but this isn’t the case.
navigating to email.siteb.domain.com/owa also redirects to email.domain.com - which is an entirely different VIP on a different loadbalancer. Navigating to mail.domain.com (a legacy OWA url navigates normally and does not revert back to email.domain.com). Is this simply explained anywhere and where should I look in my config for this to be happening? I don’t believe this is an exchange issue as it only happens internally with clients directly to the LB.