jammy (1) nbdkit-cdi-plugin.1.gz

Provided by: nbdkit_1.24.1-2ubuntu4_amd64 bug

NAME
       nbdkit-cdi-plugin - export a layer from a container image


SYNOPSIS
        nbdkit cdi [name=]NAME[:TAG|@DIGEST] [layer=N]


DESCRIPTION
       "nbdkit-cdi-plugin" (Containerized Data Importer plugin) is a plugin for nbdkit(1) which downloads a
       container image using podman-pull(1) and makes a single layer available over NBD.  The plugin is
       essentially a convenient wrapper around podman(1) and jq(1) and requires both tools to be installed.


EXAMPLES
       Given a Containerized Data Importer (CDI) registry image containing a VM disk, you can export the whole
       layer using:

        $ nbdkit cdi docker://kubevirt/fedora-cloud-container-disk-demo

       The layer exported over NBD is a tar file:

        $ nbdcopy nbd://localhost - | file -
        -: POSIX tar archive

       To export only the VM disk image in this layer, combine this plugin with nbdkit-tar-filter(1).  In this
       example when you run file(1) on the tar entry within the layer it shows that it is a QCOW2 file:

        $ nbdkit cdi docker://kubevirt/fedora-cloud-container-disk-demo \
                --filter=tar tar-entry=./disk/downloaded \
                --run 'nbdcopy "$uri" - | file -'
        -: QEMU QCOW2 Image (v2), 4294967296 bytes


PARAMETERS
       [name=]NAME[:TAG|@DIGEST]
           The name or URI of the container image.  This is passed to podman-pull(1).

           "name=" is a magic config key and may be omitted in most cases.  See "Magic parameters" in nbdkit(1).

       layer=N
           Export the N'th layer (instead of layer 0).


ENVIRONMENT VARIABLES
       "TMPDIR"
           A temporary copy of the layer is created in "TMPDIR".  If this environment variable is not set then
           /var/tmp is used instead.


FILES
       $plugindir/nbdkit-cdi-plugin.so
           The plugin.

           Use "nbdkit --dump-config" to find the location of $plugindir.


VERSION
       "nbdkit-cdi-plugin" first appeared in nbdkit 1.22.


SEE ALSO
       nbdkit(1), nbdkit-plugin(3), nbdkit-tar-filter(1), podman(1), podman-pull(1), jq(1),
       https://github.com/kubevirt/containerized-data-importer/blob/master/doc/image-from-registry.md.


AUTHORS
       Richard W.M. Jones


       Copyright (C) 2020 Red Hat Inc.


LICENSE
       Redistribution and use in source and binary forms, with or without modification, are permitted provided
       that the following conditions are met:

       •   Redistributions of source code must retain the above copyright notice, this list of conditions and
           the following disclaimer.

       •   Redistributions in binary form must reproduce the above copyright notice, this list of conditions and
           the following disclaimer in the documentation and/or other materials provided with the distribution.

       •   Neither the name of Red Hat nor the names of its contributors may be used to endorse or promote
           products derived from this software without specific prior written permission.

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       INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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