55952c8605
This builds upon commit ea452d7ced.
The configuration of a toolbox container is a higher level topic than
the entry point, and the entry point is mentioned as one part of it.
Therefore, putting the section on toolbox set-up earlier in the text
makes it nicely flow from the DESCRIPTION section into the Entry Point
sub-section.
Emphasize the user-visible features of a toolbox container, and not
the underlying implementation details, and avoid using too much jargon
about container technology.
https://github.com/containers/toolbox/pull/814
4.6 KiB
% toolbox-create(1)
NAME
toolbox-create - Create a new toolbox container
SYNOPSIS
toolbox create [--distro DISTRO | -d DISTRO] [--image NAME | -i NAME] [--release RELEASE | -r RELEASE] [CONTAINER]
DESCRIPTION
Creates a new toolbox container. You can then use the toolbox enter command
to interact with the container at any point.
A toolbox container is an OCI container created from an OCI image. On Fedora,
the default image is known as fedora-toolbox:N, where N is the release of
the host. If the image is not present locally, then it is pulled from a
well-known registry like registry.fedoraproject.org. Other images may be
used on other host operating systems. If the host is not recognized, then the
Fedora image will be used.
The container is created with podman create, and its entry point is set to
toolbox init-container.
By default, a toolbox container is named after its corresponding image. If the image had a tag, then the tag is included in the name of the container, but it's separated by a hyphen, not a colon. A different name can be assigned by using the CONTAINER argument.
Container Configuration
A toolbox container seamlessly integrates with the rest of the operating system by providing access to the user's home directory, the Wayland and X11 sockets, networking (including Avahi), removable devices (like USB sticks), systemd journal, SSH agent, D-Bus, ulimits, /dev and the udev database, etc..
The user ID and account details from the host is propagated into the toolbox container, SELinux label separation is disabled, and the host file system can be accessed by the container at /run/host. The container has access to the host's Kerberos credentials cache if it's configured to use KCM caches.
A toolbox container can be identified by the com.github.containers.toolbox
label or the /run/.toolboxenv file.
The entry point of a toolbox container is the toolbox init-container command
which plays a role in setting up the container, along with the options passed
to podman create.
Entry Point
A key feature of toolbox containers is their entry point, the toolbox init-container command.
OCI containers are inherently immutable. Configuration options passed through
podman create are baked into the definition of the OCI container, and can't
be changed later. This means that changes and improvements made in newer
versions of Toolbox can't be applied to pre-existing toolbox containers
created by older versions of Toolbox. This is avoided by using the entry point
to configure the container at runtime.
The entry point of a toolbox container customizes the container to fit the
current user by ensuring that it has a user that matches the one on the host,
and grants it sudo and root access.
Crucial configuration files, such as /etc/host.conf, /etc/hosts,
/etc/localtime, /etc/resolv.conf and /etc/timezone, inside the container
are kept synchronized with the host. The entry point also bind mounts various
subsets of the host's filesystem hierarchy to their corresponding locations
inside the container to provide seamless integration with the host. This
includes /run/libvirt, /run/systemd/journal, /run/udev/data,
/var/lib/libvirt, /var/lib/systemd/coredump, /var/log/journal and others.
On some host operating systems, important paths like /home, /media or
/mnt are symbolic links to other locations. The entry point ensures that
paths inside the container match those on the host, to avoid needless
confusion.
OPTIONS
--distro DISTRO, -d DISTRO
Create a toolbox container for a different operating system DISTRO than the
host. Cannot be used with --image.
--image NAME, -i NAME
Change the NAME of the base image used to create the toolbox container. This
is useful for creating containers from custom-built base images. Cannot be used
used with --release.
If NAME does not contain a registry, the local image storage will be consulted, and if it's not present there then it will be pulled from a suitable remote registry.
--release RELEASE, -r RELEASE
Create a toolbox container for a different operating system RELEASE than the
host. Cannot be used with --image.
EXAMPLES
Create a toolbox container using the default image matching the host OS
$ toolbox create
Create a toolbox container using the default image for Fedora 30
$ toolbox create --distro fedora --release f30
Create a custom toolbox container from a custom image
$ toolbox create --image bar foo
SEE ALSO
toolbox(1), toolbox-init-container(1), podman(1), podman-create(1)