92cc1a15d6
Now that toolbox containers no longer use a separate PID namespace [1],
the entry point specified in 'podman create ...' doesn't act as PID 1
inside the toolbox container. It's just a process that's spawned by
'podman start' to denote the state of the container. This opens the
possibility of using something even more lightweight, such as
'sleep +Inf'.
sleep(1) takes 64 kB compared to the 432 kB taken by /bin/sh.
This wouldn't have been possible with a separate PID namespace. In that
case, the entry point would also become PID 1, and since the only
signals that can be sent to a PID 1 are those for which it has
explicitly installed handlers, this would cause various problems.
[1] Commit
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| data | ||
| doc | ||
| images/fedora | ||
| .travis.yml | ||
| COPYING | ||
| gen-docs-list | ||
| meson.build | ||
| NEWS | ||
| README.md | ||
| toolbox | ||
| toolbox-sudo | ||
Toolbox is a tool that offers a familiar RPM based environment for developing and debugging software that runs fully unprivileged using Podman.
The toolbox container is a fully mutable container; when you see
yum install ansible for example, that's something you can do inside your
toolbox container, without affecting the base operating system.
This is particularly useful on OSTree based Fedora systems like Silverblue. The intention of these systems is to discourage installation of software on the host, and instead install software as (or in) containers.
However, this tool doesn't require using an OSTree based system — it works equally well if you're running e.g. existing Fedora Workstation or Server, and that's a useful way to incrementally adopt containerization.
The toolbox environment is based on an OCI
image. On Fedora this is the fedora-toolbox image. This image is then
customized for the current user to create a toolbox container that seamlessly
integrates with the rest of the operating system.
Usage
Create your toolbox container:
[user@hostname ~]$ toolbox create
[user@hostname ~]$
This will create a container, and an image, called
fedora-toolbox-<your-username>:<version-id> that's specifically customised
for your host user.
Enter the toolbox:
[user@hostname ~]$ toolbox enter
🔹[user@toolbox ~]$