NAME¶

podman-play-kube - Create containers, pods or volumes based on Kubernetes YAML

SYNOPSIS¶

podman play kube [options] file.yml|-

DESCRIPTION¶

podman play kube will read in a structured file of Kubernetes YAML. It will then recreate the containers, pods or volumes described in the YAML. Containers within a pod are then started and the ID of the new Pod or the name of the new Volume is output. If the yaml file is specified as "-" then podman play kube will read the YAML file from stdin. Using the --down command line option, it is also capable of tearing down the pods created by a previous run of podman play kube. Ideally the input file would be one created by Podman (see podman-generate-kube(1)). This would guarantee a smooth import and expected results.

Currently, the supported Kubernetes kinds are: - Pod - Deployment - PersistentVolumeClaim - ConfigMap

Kubernetes Pods or Deployments

Only two volume types are supported by play kube, the hostPath and persistentVolumeClaim volume types. For the hostPath volume type, only the default (empty), DirectoryOrCreate, Directory, FileOrCreate, File, and Socket subtypes are supported. The CharDevice and BlockDevice subtypes are not supported. Podman interprets the value of hostPath path as a file path when it contains at least one forward slash, otherwise Podman treats the value as the name of a named volume. When using a persistentVolumeClaim, the value for claimName is the name for the Podman named volume.

Note: When playing a kube YAML with init containers, the init container will be created with init type value always.

Note: hostPath volume types created by play kube will be given an SELinux private label (Z)

Note: If the :latest tag is used, Podman will attempt to pull the image from a registry. If the image was built locally with Podman or Buildah, it will have localhost as the domain, in that case, Podman will use the image from the local store even if it has the :latest tag.

Kubernetes PersistentVolumeClaims

A Kubernetes PersistentVolumeClaim represents a Podman named volume. Only the PersistentVolumeClaim name is required by Podman to create a volume. Kubernetes annotations can be used to make use of the available options for Podman volumes.

Play kube is capable of building images on the fly given the correct directory layout and Containerfiles. This option is not available for remote clients yet. Consider the following excerpt from a YAML file:

apiVersion: v1
kind: Pod
metadata:
spec:


  containers:


  - command:


    - top


    - name: container


      value: podman


    image: foobar

If there is a directory named foobar in the current working directory with a file named Containerfile or Dockerfile, Podman play kube will build that image and name it foobar. An example directory structure for this example would look like:

|- mykubefiles


    |- myplayfile.yaml


    |- foobar


         |- Containerfile

The build will consider foobar to be the context directory for the build. If there is an image in local storage called foobar, the image will not be built unless the --build flag is used.

Kubernetes ConfigMap

Kubernetes ConfigMap can be referred as a source of environment variables in Pods or Deployments.

For example ConfigMap defined in following YAML:

apiVersion: v1
kind: ConfigMap
metadata:


  name: foo
data:


    FOO: bar

can be referred in a Pod in following way:

apiVersion: v1
kind: Pod
metadata:
spec:


  containers:


  - command:


    - top


    name: container-1


    image: foobar


    envFrom:


      - configMapRef:


      name: foo


      optional: false

and as a result environment variable FOO will be set to bar for container container-1.

OPTIONS¶

EXAMPLES¶

Recreate the pod and containers as described in a file called demo.yml

$ podman play kube demo.yml
52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6

Recreate the pod and containers as described in a file demo.yml sent to stdin

$ cat demo.yml | podman play kube -
52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6

Teardown the pod and containers as described in a file demo.yml

$  podman play kube --down demo.yml
Pods stopped:
52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
Pods removed:
52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6

Provide configmap-foo.yml and configmap-bar.yml as sources for environment variables within the containers.

$ podman play kube demo.yml --configmap configmap-foo.yml,configmap-bar.yml
52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
$ podman play kube demo.yml --configmap configmap-foo.yml --configmap configmap-bar.yml
52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6

CNI network(s) can be specified as comma-separated list using --network

$ podman play kube demo.yml --network cni1,cni2
52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6

Please take into account that CNI networks must be created first using podman-network-create(1).

SEE ALSO¶

podman(1), podman-container(1), podman-pod(1), podman-generate-kube(1), podman-play(1), podman-network-create(1), containers-certs.d(5)

HISTORY¶

December 2018, Originally compiled by Brent Baude (bbaude at redhat dot com)