[Error] Not able to change hostname in init_hooks

[briandipalma]

[Error] Not able to change hostname in init_hooks

[michaelhaaf]

I think this is partially a typo/error in the init-hook provided in the documentation: https://github.com/89luca89/distrobox/blob/main/docs/useful_tips.md#enable-ssh-x-forwarding-when-ssh-ing-in-a-distrobox

I think command substitution here is misplaced, uname -n already prints to stdout and can be redirected directly. Or you can use echo on the provided command. I.e.

uname -n > /etc/hostname
echo "$(uname -n)" > /etc/hostname

Tested on Fedora 39 below:

# Also tested the 'echo "$(uname -n)" > /etc/hostname' with the same result

user@hostname $ distrobox create --image ghcr.io/username/sample-image:latest -n box-name \ 
    --init-hooks 'uname -n > /etc/hostname' && distrobox enter box-name

...

Setting up groups...                    	 [ OK ]
Setting up users...                     	 [ OK ]
Setting up skel...                      	 [ OK ]
Executing init hooks...                 	 [ OK ]

Container Setup Complete!

[email protected] $ cat /etc/hostname 
box-name.hostname

[email protected] $ hostname
box-name.hostname  

It works! Sort of? For reasons that may make sense but are beyond me at the moment, the resulting hostname is a FQDN (the container name as a subdomain of the hostname).

What I mean is, I would rather expect the outcome of uname -n > /etc/hostname to be:

[email protected] $ cat /etc/hostname 
hostname

[michaelhaaf]

In the time since making that comment I've come to thinking/realizing a few things:

(1) It's probably fine that the result of this init-hook method creates a new FQDN for the intents and purposes of both resolving to the host name and being unique/individually identifiable on a local network (i.e. there's nothing wrong with boxname.hostname).

It turns out there's already been quite a lot of discussion about this in this repo and in toolbox which I only skimmed, but the important parts seem to work (e.g. ssh -x forwarding) in this scheme.

(2) The documentation has a typo, which is a separate issue that I also had run into when trying this out (which is why I knew the fix). I've made a pull request to address this here.

(3) OP floated the idea of having a --hostname parameter rather thatn using init-hook which seems like a reasonable feature, e.g. docker-compose has this. There may already be a feature request tracking this if you look.

[briandipalma]

1. boxname.hostname is the hostname that is set in the container by default. I saw the other issues that talked about hostname setting, that's where I got some of my attempted solutions.

2. The --hostname flag is what distrobox uses to tell podman/docker what hostname to set in the container (boxname.hostname by default).

In fact I ended up solving the issue using that flag. I replaced the distrobox.ini file I was using during the creating of my container with a script that overrides the --hostname flag distrobox passes into the container runner.

distrobox rm env --force;

distrobox create --image docker.io/briandipalma/env:latest \
	--name env \
	--pull \
	--additional-flags "--hostname ${HOSTNAME}" \
	--pre-init-hooks "SHELL=/usr/bin/fish";

distrobox enter env;

I'll close the issue as I've a solution that I'm happy with.

[redbeardymcgee]

In fact I ended up solving the issue using that flag. I replaced the distrobox.ini file I was using during the creating of my container with a script that overrides the --hostname flag distrobox passes into the container runner.

I have additional_flags="--hostname <sub.domain>"

I ended up in this issue because I was looking for a way to use command substitution in init_hooks. To bootstrap my devbox, I use sh -c "$(curl -fsLS get.chezmoi.io)" -- -b $HOME/.local/bin. This fails with the error tmpdir: parameter not set.

This is probably the culprit, sort of. I'm not sure how tmpdir is unset because the variable does get set.

I thought perhaps it's because mktemp might be missing. Try adding additional_packages=coreutils or init_hooks="sudo dnf install -y coreutils" (or pre_init_hooks). Still breaks.

Take the command substitution out.

init_hooks="curl -sSLf get.chezmoi.io -o chezmoi-installer;"
init_hooks="chmod +x ./chezmoi-installer;"
init_hooks='./chezmoi-installer -b "/home/redbeardymcgee/devbox/.local/bin" init redbeardymcgee --ssh --apply --promptDefaults --force;'

Creating './chezmoi-installer -b " ${init_hooks}' using image registry.fedoraproject.org/fedora-toolbox:latest /home/josh/.local/bin/distrobox-create: 1: eval: init_hooks: parameter not set

Huh?