I have a barracuda load balancer and a VIP which in turn forwards to a cluster of servers. Each of these servers has the VIP added to the loopback interface as the load balancer is on direct server response.
I've been using this method for almost a couple years without a problem, however the other day I needed to add an additional IP address to the cluster/load balancer. I added the loopback interface before I put it on the load balancer.
The problem now is that if I try to go to public-ip-here:80 it works perfectly fine though, as if it's not a loopback? I can ssh to the ip and any other service as well. If I add it to my load balancer and try to forward it the way I am my other servers, it will connect directly to the server instead of using the load balancer as expected.
Here is an example of the interface with the actual public IP redacted:
lo:6 Link encap:Local Loopback inet addr:18.104.22.168 Mask:255.255.255.255 UP LOOPBACK RUNNING MTU:16436 Metric:1
I'm at a loss on how to fix this and google has not been much help.