toolbox – bring your tools with you

rhcos-toolbox is a small script, designed for RHEL CoreOS, that launches a podman container to let you bring in your favorite debugging or admin tools.

Usage

$ /usr/bin/toolbox
Spawning container core-fedora-latest on /var/lib/toolbox/core-fedora-latest.
Press ^] three times within 1s to kill container.
[root@localhost ~]# dnf -y install tcpdump
...
[root@localhost ~]# tcpdump -i ens3
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on ens3, link-type EN10MB (Ethernet), capture size 65535 bytes

Advanced Usage

Use a custom image

toolbox uses a Fedora-based userspace environment by default, but this can be changed to any Docker image. Simply override environment variables in $HOME/.toolboxrc:

core@core-01 ~ $ cat ~/.toolboxrc
REGISTRY=registry.redhat.io
IMAGE=rhel7/rhel-tools:latest
core@core-01 ~ $ toolbox
Spawning a container 'toolbox-test' with image 'registry.redhat.io/rhel7/rhel-tools:latest'

Automatically enter toolbox on login

Set an /etc/passwd entry for one of the users to /usr/bin/toolbox:

useradd bob -m -p '*' -s /usr/bin/toolbox -U -G sudo,docker,rkt

Now when SSHing into the system as that user, toolbox will automatically be started:

$ ssh bob@hostname.example.com
Container Linux by CoreOS alpha (1284.0.0)
...
Spawning container bob-fedora-latest on /var/lib/toolbox/bob-fedora-latest.
Press ^] three times within 1s to kill container.
[root@localhost ~]# dnf -y install emacs-nox
...
[root@localhost ~]# emacs /media/root/etc/systemd/system/docker.service