help me understand something about load balancing.
Let's pretend we have one server as frontend and three servers as backend.
All are hosted in the same datacenter using a local connectivity. Usually VPSes are served with a 1Gbps port, if you experience high traffic all the backend servers will try to transfer traffic to the frontend proxy at a maximum of 3Gbps total while the frontend will only be able to accept 1Gbps. Wouldn't this make things slower in the end for the users?
Plus is the local network used between servers the same as the one connected to the Internet which is always shared?
If we instead consider backend servers on different locations would it be possible to load balance with a real "IP redirect" instead of proxying? Or is a CDN the only way to achieve that? I'd imagine that using a proxy config in different locations wouldn't make any sense since you add latency, travel time and there's no proximity advantage for the users since traffic will all originate from one location (the frontend)