[wpietri]

I agree with parts of this, sort of.

I maintain a personal server that hosts a variety of VMs for things like mail, static site hosting, nameservice, etc. Last time I rebuilt it, I thought, hey, I'll try doing it with these interesting tools. The immutable-infrastructure approach turns out to be pretty heavy in that case. A lot of times it feels like I have to perform a triple bank shot just to make a minor configuration change.

That said, I think the one-off server, carefully maintained by one person, is becoming very rare. When I build things that other people will work on, I think immutable infrastructure and the cattle-not-pets approach is the only responsible way to go. Even if traffic volume won't be huge, I think the clarity and ease of debugging you get is vital when it doesn't all live in one wizard's head.

I agree that stateful servers are a challenge in this context. But they're a challenge regardless. Having that one thing we're afraid to upgrade or restart can cause all sorts of development and business process issues. That might have been a worthwhile tradeoff 10 years ago when you had to buy all your hardware and you needed ops people to do a lot of stuff manually. Servers go down, and we might as well accept that from the beginning.