umoci-raw-runtime-config(1)(#)  runtime-config  umoci-raw-runtime-config(1)(#)

Aleksa Sarai DECEMBER 2016


NAME
       umoci raw runtime-config - Generate an OCI runtime configuration for an
       image



SYNOPSIS
       umoci raw runtime-config --image=image[:tag] [--rootfs=rootfs]
       [--rootless] config


       umoci raw config --image=image[:tag] [--rootfs=rootfs] [--rootless]
       config



DESCRIPTION
       Generate a new OCI runtime configuration from an image, without
       extracting the rootfs of said image. The configuration is written to
       the path given by config, overwriting it if it exists already. This is
       one of the operations done by umoci-unpack(1) when generating the
       runtime bundle, but because of the overhead of extracting a root
       filesystem, umoci-unpack(1) is not practical to be used many times if
       the user doesn't actually want to use the root filesystem. Some fields
       require a root filesystem as a "source of truth", and a source root
       filesystem can be specified using --rootfs. The other flags have the
       same effects as with umoci-unpack(1).


       Note however that the output of umoci-raw-runtime-config(1) is not
       necessarily identical to the output from umoci-unpack(1). This is
       especially true if --rootfs is not specified, which results in umoci(1)
       leaving fields in the runtime spec to their defaults if computing their
       values would require using the root filesystem as a source-of-truth.



OPTIONS
       The global options are defined in umoci(1).


       --image=image[:tag]
         The OCI image tag which will be extracted to the bundle. image must
       be a
         path to a valid OCI image and tag must be a valid tag in the image.
       If
         tag is not provided it defaults to "latest".


       --rootfs=rootfs
         Use rootfs as a secondary source of truth when generating the runtime
         configuration (this is especially important for Config.User
       conversion). If
         unspecified, any runtime fields that require a secondary source of
       truth to
         be filled with be left in their default values. This may result in
         discrepancies between the output of umoci-unpack(1) and
         umoci-raw-runtime-config(1).


       --rootless
         Generate a rootless container configuration, similar to the
       configuration
         produced by umoci-unpack(1) when provided the --rootless flag.



EXAMPLE
       The following downloads an image from a docker(1) registry using
       skopeo(1) and then generates the config.json for that image.



              % skopeo copy docker://opensuse/amd64:42.2 oci:image:latest
              % umoci raw runtime-config --image image:latest config.json



       If a root filesystem is already present, it is possible to specify it
       with the --rootfs flag. This will source the root filesystem for
       conversion operations that necessitate it.



              % skopeo copy docker://opensuse/amd64:42.2 oci:image:latest
              # umoci unpack --image image bundle
              % umoci raw runtime-config --image image --rootfs bundle/rootfs config.json




SEE ALSO
       umoci(1), umoci-repack(1), runc(8)

raw                                  umoci      umoci-raw-runtime-config(1)(#)