NAME

       buildah-unshare - Run a command inside of a modified user namespace.

SYNOPSIS

       buildah unshare [options] [--] [command]

DESCRIPTION

       Launches  a  process  (by  default, $SHELL) in a new user namespace.  The user namespace is configured so
       that the invoking user's UID and primary GID appear to be UID 0 and  GID  0,  respectively.   Any  ranges
       which  match that user and group in /etc/subuid and /etc/subgid are also mapped in as themselves with the
       help of the newuidmap(1) and newgidmap(1) helpers.

       buildah unshare is useful for troubleshooting unprivileged operations and for manually  clearing  storage
       and other data related to images and containers.

       It  is  also useful if you want to use the buildah mount command.  If an unprivileged user wants to mount
       and work with a container, then they need to execute buildah unshare.  Executing buildah mount fails  for
       unprivileged users unless the user is running inside a buildah unshare session.

OPTIONS

       --mount, -m [VARIABLE=]containerNameOrID

       Mount the containerNameOrID container while running command, and set the environment variable VARIABLE to
       the  path  of  the mountpoint.  If VARIABLE is not specified, it defaults to containerNameOrID, which may
       not be a valid name for an environment variable.

EXAMPLE

       buildah unshare id

       buildah unshare pwd

       buildah unshare cat /proc/self/uid_map /proc/self/gid_map

       buildah unshare rm -fr $HOME/.local/share/containers/storage /run/user/`id -u`/run

       buildah unshare --mount containerID sh -c 'cat ${containerID}/etc/os-release'

       If you want to use buildah with a mount command then you can create a script that looks something like:

       cat buildah-script.sh << _EOF
       #!/bin/sh
       ctr=$(buildah from scratch)
       mnt=$(buildah mount $ctr)
       dnf -y install --installroot=$mnt PACKAGES
       dnf -y clean all --installroot=$mnt
       buildah config --entrypoint="/bin/PACKAGE" --env "FOO=BAR" $ctr
       buildah commit $ctr imagename
       buildah unmount $ctr
       _EOF

       Then execute it with:

       buildah unshare buildah-script.sh

SEE ALSO

       buildah(1), buildah-mount(1), namespaces(7), newuidmap(1), newgidmap(1), user_namespaces(7)

buildah                                             June 2018                                 buildah-unshare(1)