You pay a datacenter to put it in a rack and add connect power and uplinks, then treat it like a big ec2 instance (minus the built-in firewall). Now you just need someone who knows how to secure an ec2 instance and run your preferred software there (with failover and stuff).
If you run a single-digit number of servers and replace them every 5 years you will probably never get a hardware failure. If you're unlucky and it still happens get someone to diagnose what's wrong, ship replacement parts to the data center and pay their tech to install them in your server.
Bare metal at scale is difficult. A small number of bare metal servers is easy. If your needs are average enough you can even just rent them so you don't have capital costs and aren't responsible for fixing hardware issues.
Are you going to risk your entire business over "probably never get a hardware failure" that, if it hits, might result in days of downtime to resolve? I wouldn't.
Just pay 2x for the hardware and have a hot standby, 1990s-style. Practice switching between the boxes every month or so; should be imperceptible for the customers and a nearly non-event for the ops.
How many hours of labor does that take every month you failover? What about hot hard drive spares? Do you want networking redundancy? How about data backups? Second set of hot servers in another physical data center?
All of that costs money and time. You're probably better off using cloud hosting and focusing on your unique offering than having that expertise and coordination in house.
sounds like an opportunity for someone (you?) to offer an abstraction slightly above bare metal to do the stuff you said to do, charging higher than bare metal but lower than the other stuff. how much daylight is there between those prices?
If you run a single-digit number of servers and replace them every 5 years you will probably never get a hardware failure. If you're unlucky and it still happens get someone to diagnose what's wrong, ship replacement parts to the data center and pay their tech to install them in your server.
Bare metal at scale is difficult. A small number of bare metal servers is easy. If your needs are average enough you can even just rent them so you don't have capital costs and aren't responsible for fixing hardware issues.