gotcha when changing hostname
hehe, so ... if you ever change the hostname of a Linux machine, you really really ought to double-check /etc/hosts to make the same hostname change there
it's surprising just how much will break if a machine's own hostname isn't resolvable to a 127.x.x.x address :P
22 replies
Isn't this what hostnamectl is supposed to handle?
it modifies /etc/hostname for you, but doesn't seem to touch /etc/hosts
i still prefer hostnamectl, but i'm now unsure of what benefit it offers over editing /etc/hostname directly
Interesting. I’ve changed my hostname on a few machines throughout the past and never ran into this. Good to know if I ever run into this in the future.
https://man7.org/linux/man-pages/man1/hostnamectl.1.html
I know this is the preferred way to do it now, but I sometimes worry that abstracting where things are configured in an is that configures everything in a file.
You used to only have to check two places to change a hostname.
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Laughs in Alpine.
Laughs louder in Void, Gentoo, and Devuan.
yep, I used that command to modify the hostname, rather than edit /etc/hostname directly
There's another way to change the hostname that isn't etc/hosts?
Probably a systemd-somethingd.
Edit: yup
no, you might have misunderstood
/etc/hosts is not where the hostname is configured
/etc/hostname for the actual hostname, and a mapping in /etc/hosts pointing it at a 127.x.x.x address
Ohh right yes. I only ever touch hostname once during install and then only hosts after that
Nothing is worse than waiting for sudo to time out. I forget how long it would take, but it always feels like ages.
This reminds me... My server demands to be known as hostname.local on my network. The other machines just respond to just hostname. I really should figure out why that is.
Domain search suffixes
I use DHCP for everything, even my server, with a reserved IP address in the router for the server and my desktop and a few other things I don't want to move around (printers, some IoT things, Home Assistant, etc.).
I think the issue is the bridge interface I have to set up for Home Assistant.
Lost my mind a few years ago over this quirk. Now I always change both files when I want to change the hostname.
You guys are having own hostname in hosts file?
Never, there's no need for it. I can reach it with localhost or 127.0.0.1, so why would I even put it in?
seems like a pretty common practice across Linux distributions
/etc/hostname for the actual hostname, and a mapping in /etc/hosts pointing it at a 127.x.x.x address
If you have myhostname set for hosts in /etc/nsswitch.conf it shall take care of this for you (should be the default on most systemd distros I believe? not sure)
It’s always been wild to me how the seemingly-simplest change (“what is the name of this computer”) has so many little gotchas and quirks.