I updated a server cluster last night and was getting loads of

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

warnings. You get told about the offending line number:

Offending RSA key in ~/.ssh/known_hosts:531

And usually I’d just edit it and be done, but after doing it a couple of times I wrote unknown-host:

so I wouldn’t have to do that again, in the great spirit of xkcd’s “Automation” webcomic

xkcd webcomic about how writing a simple script to automate a task grows exponentially