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

75 points · 22 comments · view on lemmy.world

22 Comments

JasonDJ@lemmy.zip · 12 pts · 178d (1 reply)

Isn't this what hostnamectl is supposed to handle?

jokeyrhyme@lemmy.ml · 3 pts · 177d

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

otacon239@lemmy.world · 9 pts · 178d

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.

ark3@lemmy.dbzer0.com · 9 pts · 178d (4 replies)
non_burglar@lemmy.world · 5 pts · 178d

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.

Oldmanyellsatsky.jpg

MonkderVierte@lemmy.zip · 4 pts · 177d (1 reply)

Laughs in Alpine.

racketlauncher831@lemmy.ml · 1 pts · 176d

Laughs louder in Void, Gentoo, and Devuan.

jokeyrhyme@lemmy.ml · 3 pts · 178d

yep, I used that command to modify the hostname, rather than edit /etc/hostname directly

luthis@lemmy.nz · 7 pts · 177d (3 replies)

There's another way to change the hostname that isn't etc/hosts?

MonkderVierte@lemmy.zip · 5 pts · 177d

Probably a systemd-somethingd.

Edit: yup

jokeyrhyme@lemmy.ml · 4 pts · 177d (1 reply)

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

luthis@lemmy.nz · 2 pts · 176d

Ohh right yes. I only ever touch hostname once during install and then only hosts after that

fuckwit_mcbumcrumble@lemmy.dbzer0.com · 5 pts · 178d

Nothing is worse than waiting for sudo to time out. I forget how long it would take, but it always feels like ages.

limelight79@lemmy.world · 5 pts · 177d (2 replies)

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.

p03locke@lemmy.dbzer0.com · 4 pts · 177d (1 reply)

Domain search suffixes

limelight79@lemmy.world · 1 pts · 175d

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.

monovergent@lemmy.ml · 4 pts · 178d

Lost my mind a few years ago over this quirk. Now I always change both files when I want to change the hostname.

arty@feddit.org · 4 pts · 177d (2 replies)

You guys are having own hostname in hosts file?

itmosi@sh.itjust.works · 2 pts · 176d

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?

jokeyrhyme@lemmy.ml · 1 pts · 177d

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

alastel@lemmy.ml · 2 pts · 178d

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)

Hawke@lemmy.world · 2 pts · 178d

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.