I always wonder just how much can a single load balancer do? Even if it is just forwarding request/replies, at something like hundreds of thousands of queries per second how does it work?
Secondly, if you want you can still have multiple load balancers listen to a single IP; it’s a bit more tricky to pull that off with HTTP load balancing rather than just network load balancing, but not impossible.
Example of a load balancer appliance that allows multiple load balancers to share a single IP: https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-admin/h...
Unimog is key to making the deployment described in the paper work.
Another way of thinking about this is that we have a single virtual load balancer (backed by all the physical machines in the DC) sitting in front of services that transform/terminate/filter/etc customer traffic.
At the edges, your switches or border routers announce the IP to all your peers and transit ISPs.