The pieces aren't difficult in isolation, but the combined logistical total cost of operational ownership is high and includes huge tail risks. When your metal fails, it stays down until physically fixed. Depending on your business, that's either acceptable or not.
We mitigate that risk by having our backup servers and database replicas in the cloud, but the big beefy primary machines are bare metal run on cheap Quebec power w/ unlimited 1Gbps residential bandwidth.
