Ubuntu Manpage: podman-volume-create

Provided by: podman_4.9.3+ds1-1ubuntu0.2_amd64

NAME

       podman-volume-create - Create a new volume

SYNOPSIS

       podman volume create [options] [name]

DESCRIPTION

       Creates  an  empty  volume  and  prepares  it  to be used by containers. The volume can be created with a
       specific name, if a name is not given a random name is generated. You can add metadata to the  volume  by
       using the --label flag and driver options can be set using the --opt flag.

OPTIONS

--driver, -d=driver
Specify the volume driver name (default local). There are two drivers supported by Podman itself: local
and image.

The local driver uses a directory on disk as the backend by default, but can also use the mount(8)
command to mount a filesystem as the volume if --opt is specified.

The image driver uses an image as the backing store of for the volume. An overlay filesystem is created,
which allows changes to the volume to be committed as a new layer on top of the image.

Using a value other than local or image, Podman attempts to create the volume using a volume plugin with
the given name. Such plugins must be defined in the volume_plugins section of the containers.conf(5)
configuration file.

--help
Print usage statement

--ignore
Don't fail if the named volume already exists, instead just print the name. Note that the new options are
not applied to the existing volume.

--label, -l=label
Set metadata for a volume (e.g., --label mykey=value).

--opt, -o=option
Set driver specific options. For the default driver, local, this allows a volume to be configured to
mount a filesystem on the host.

For the local driver the following options are supported: type, device, o, and [no]copy.

• The type option sets the type of the filesystem to be mounted, and is equivalent to the -t flag
to mount(8).

• The device option sets the device to be mounted, and is equivalent to the device argument to
mount(8).

• The copy option enables copying files from the container image path where the mount is created
to the newly created volume on the first run. copy is the default.

The o option sets options for the mount, and is equivalent to the filesystem options (also -o) passed to
mount(8) with the following exceptions:

• The o option supports uid and gid options to set the UID and GID of the created volume that are
not normally supported by mount(8).

• The o option supports the size option to set the maximum size of the created volume, the inodes
option to set the maximum number of inodes for the volume, and noquota to completely disable
quota support even for tracking of disk usage. The size option is supported on the "tmpfs" and
"xfs[note]" file systems. The inodes option is supported on the "xfs[note]" file systems.
Note: xfs filesystems must be mounted with the prjquota flag described in the xfs_quota(8) man
page. Podman will throw an error if they're not.

• The o option supports using volume options other than the UID/GID options with the local driver
and requires root privileges.

• The o options supports the timeout option which allows users to set a driver specific timeout in
seconds before volume creation fails. For example, --opt=o=timeout=10 sets a driver timeout of
10 seconds.

Note Do not confuse the --opt,-o create option with the -o mount option. For example, with podman volume
create, use -o=o=uid=1000 not -o=uid=1000.

For the image driver, the only supported option is image, which specifies the image the volume is based
on. This option is mandatory when using the image driver.

When not using the local and image drivers, the given options are passed directly to the volume plugin.
In this case, supported options are dictated by the plugin in question, not Podman.

EXAMPLES

       $ podman volume create myvol

       $ podman volume create

       $ podman volume create --label foo=bar myvol

       # podman volume create --opt device=tmpfs --opt type=tmpfs --opt o=size=2M,nodev,noexec myvol

       # podman volume create --opt device=tmpfs --opt type=tmpfs --opt o=uid=1000,gid=1000 testvol

       # podman volume create --driver image --opt image=fedora:latest fedoraVol

QUOTAS

       podman volume create uses XFS project quota controls for controlling the size and the number of inodes of
       builtin volumes. The directory used to store the volumes must be an XFS file system and be  mounted  with
       the pquota option.

       Example /etc/fstab entry:

       /dev/podman/podman-var /var xfs defaults,x-systemd.device-timeout=0,pquota 1 2

       Podman generates project IDs for each builtin volume, but these project IDs need to be unique for the XFS
       file system. These project IDs by default are generated randomly, with a potential for overlap with other
       quotas on the same file system.

       The xfs_quota tool can be used to assign a project ID to the storage driver directory, e.g.:

       echo 100000:/var/lib/containers/storage/overlay >> /etc/projects
       echo 200000:/var/lib/containers/storage/volumes >> /etc/projects
       echo storage:100000 >> /etc/projid
       echo volumes:200000 >> /etc/projid
       xfs_quota -x -c 'project -s storage volumes' /<xfs mount point>

       In  the  example above we are configuring the overlay storage driver for newly created containers as well
       as volumes to use project IDs with a start offset.  All containers are assigned larger project IDs  (e.g.
       >=  100000).   All  volume  assigned  project IDs larger project IDs starting with 200000.  This prevents
       xfs_quota management conflicts with containers/storage.

HISTORY

       January   2020,   updated   with   information   on  volume  plugins  by  Matthew  Heon  mheon@redhat.com
       ⟨mailto:mheon@redhat.com⟩ November 2018,  Originally  compiled  by  Urvashi  Mohnani  umohnani@redhat.com
       ⟨mailto:umohnani@redhat.com⟩

                                                                                         podman-volume-create(1)