buildah man page

Buildah — A command line tool that facilitates building OCI container images.

Synopsis

buildah [Options] COMMAND [ARG...]

Description

The Buildah package provides a command line tool which can be used to:

* Create a working container, either from scratch or using an image as a starting point.
* Mount a working container's root filesystem for manipulation.
* Unmount a working container's root filesystem.
* Use the updated contents of a container's root filesystem as a filesystem layer to create a new image.
* Delete a working container or an image.
* Rename a local container.

This tool needs to be run as the root user.

Options

--debug
Print debugging information
--help, -h
Show help
--registries-conf path
Pathname of the configuration file which specifies which container registries should be consulted when completing image names which do not include a registry or domain portion.  It is not recommended that this option be used, as the default behavior of using the system-wide configuration (/etc/containers/registries.conf) is most often preferred.
--registries-conf-dir path
Pathname of the directory which contains configuration snippets which specify registries which should be consulted when completing image names which do not include a registry or domain portion.  It is not recommended that this option be used, as the default behavior of using the system-wide configuration (/etc/containers/registries.d) is most often preferred.
--root value
Storage root dir (default: "/var/lib/containers/storage" for UID 0, "$HOME/.local/share/containers/storage" for other users) Default root dir is configured in /etc/containers/storage.conf
--runroot value
Storage state dir (default: "/var/run/containers/storage" for UID 0, "/var/run/user/$UID/run" for other users) Default state dir is configured in /etc/containers/storage.conf
--storage-driver value
Storage driver.  The default storage driver for UID 0 is configured in /etc/containers/storage.conf, and is vfs for other users. Overriding this option will cause the storage-opt settings in /etc/containers/storage.conf to be ignored.  The user must specify additional options via the --storage-opt flag.
--storage-opt value
Storage driver option, Default storage driver options are configured in /etc/containers/storage.conf
--userns-uid-map mapping
Specifies UID mappings which should be used to set ownership, at the filesytem level, on the contents of images and containers. Entries in this map take the form of one or more triples of a starting in-container UID, a corresponding starting host-level UID, and the number of consecutive IDs which the map entry represents. This option overrides the remap-uids setting in the options section of /etc/containers/storage.conf.
--userns-gid-map mapping
Specifies GID mappings which should be used to set ownership, at the filesytem level, on the contents of images and containers. Entries in this map take the form of one or more triples of a starting in-container GID, a corresponding starting host-level GID, and the number of consecutive IDs which the map entry represents. This option overrides the remap-gids setting in the options section of /etc/containers/storage.conf.
--version, -v
Print the version

Commands

Command Description
buildah-add(1) Add the contents of a file, URL, or a directory to the container.
buildah-bud(1) Build an image using instructions from Dockerfiles.
buildah-commit(1) Create an image from a working container.
buildah-config(1) Update image configuration settings.
buildah-containers(1) List the working containers and their base images.
buildah-copy(1) Copies the contents of a file, URL, or directory into a container's working directory.
buildah-from(1) Creates a new working container, either from scratch or using a specified image as a starting point.
buildah-images(1) List images in local storage.
buildah-inspect(1) Inspects the configuration of a container or image
buildah-mount(1) Mount the working container's root filesystem.
buildah-push(1) Push an image from local storage to elsewhere.
buildah-rename(1) Rename a local container.
buildah-rm(1) Removes one or more working containers.
buildah-rmi(1) Removes one or more images.
buildah-run(1) Run a command inside of the container.
buildah-tag(1) Add an additional name to a local image.
buildah-umount(1) Unmount a working container's root file system.
buildah-unshare(1) Launch a command in a user namespace with modified ID mappings.
buildah-version(1) Display the Buildah Version Information
storage.conf(5) Syntax of Container Storage configuration file

Files

storage.conf (/etc/containers/storage.conf)

storage.conf is the storage configuration file for all tools using containers/storage

The storage configuration file specifies all of the available container storage options for tools using shared container storage.

mounts.conf (/usr/share/containers/mounts.conf and optionally /etc/containers/mounts.conf)

The mounts.conf files specify volume mount directories that are automatically mounted inside containers when executing the `buildah run` or `buildah build-using-dockerfile` commands.  Container process can then use this content.  The volume mount content does not get committed to the final image.

Usually these directories are used for passing secrets or credentials required by the package software to access remote package repositories.

For example, a mounts.conf with the line "`/usr/share/rhel/secrets:/run/secrets`", the content of `/usr/share/rhel/secrets` directory is mounted on `/run/secrets` inside the container.  This mountpoint allows Red Hat Enterprise Linux subscriptions from the host to be used within the container.

Note this is not a volume mount. The content of the volumes is copied into container storage, not bind mounted directly from the host.

registries.conf (/etc/containers/registries.conf)

registries.conf is the configuration file which specifies which container registries should be consulted when completing image names which do not include a registry or domain portion.

See Also

podman(1), mounts.conf(5), newuidmap(1), newgidmap(1), registries.conf(5), storage.conf(5)

History

December 2017, Originally compiled by Tom Sweeney  ⟨tsweeney@redhat.com⟩

Referenced By

buildah-add(1), buildah-bud(1), buildah-commit(1), buildah-config(1), buildah-containers(1), buildah-copy(1), buildah-from(1), buildah-images(1), buildah-inspect(1), buildah-mount(1), buildah-pull(1), buildah-push(1), buildah-rename(1), buildah-rm(1), buildah-rmi(1), buildah-run(1), buildah-tag(1), buildah-umount(1), buildah-unshare(1), buildah-version(1), podman-build(1).

March 2017 buildah