All the cool kids use it to set up networks,
Well, I'm not a cool kid, I am a old war horse who cut his teeth on BIND many, many years ago. And for what it's worth, the number of clients who need the same thing is not a complex situation, its just a simple situation writ large. Maybe dnsmasq might have worked for me, but I already have BIND running the way I wanted it to run, and isc-dhcp-server is a small footprint service which will do the balance of what I need.
For what it's worth,
I got isc-dhcp-server running on it's own Debian 11 VM. I never claimed to be up-to-date on the new cool tools. I was simply saying I know IP provisioning like other folks know how to walk.
As far as the apt-get install issue that others say it wasn't an error message. Well,
respectfully, I disagree.
The installer should have stopped with a text message saying something like, OK, you're good, and from here the fails to load messages you see with be because you need to configure two files. And the message should stay on the screen until the installer acknowledges the message.
As far as
The wiki is not meant to be exhaustive.
I find that a bit silly, for two reasons. First it provides misleading information. Second it fails to provide the initial critical information. What it does provide belongs in the exhaustive material. Hubris of those who have done something before can create a sense of 'hey you should know better.' I got it working, not for anything I got here, but because I worked through the error messages, the text in the two config files and a lot of trial and error.