[cordite]

I once put `shutdown -h now` (halt) instead of `shutdown -r now` (reboot)

Once I realized what had happened on the production server I ended up calling OVH (and they were helpful but not immediately acting).

It's not a good feeling.

[icebraining]

I tend to use /sbin/reboot instead, it amounts to the same (calls shutdown), but it's harder to get it mixed up.

[smtddr]

This happened to me once; I don't know if this works on all linux distros but if you quickly follow a halt/shutdown with a "sudo init 6"(reboot) before your ssh-session gets SIGTERMed/KILLed, the box comes back up. This at least worked on some Ubuntu version a few years back.

Give it a try on some system that's not critically important :)

[cordite]

Yeah, but the problem is when you honestly didn't realize calling a halting shutdown until the server doesn't come back 5 minutes later and then you review the terminal