NAME¶

podman-kube-generate - Generate Kubernetes YAML based on containers, pods or volumes

SYNOPSIS¶

podman kube generate [options] container... | pod... | volume...

DESCRIPTION¶

podman kube generate generates Kubernetes YAML (v1 specification) from Podman containers, pods or volumes. Regardless of whether the input is for containers or pods, Podman generates the specification as a Pod by default. The input may be in the form of one or more containers, pods or volumes names or IDs.

Podman Containers or Pods

Volumes appear in the generated YAML according to two different volume types. Bind-mounted volumes become hostPath volume types and named volumes become persistentVolumeClaim volume types. Generated hostPath volume types are one of three subtypes depending on the state of the host path: DirectoryOrCreate when no file or directory exists at the host, Directory when host path is a directory, or File when host path is a file. The value for claimName for a persistentVolumeClaim is the name of the named volume registered in Podman.

Potential name conflicts between volumes are avoided by using a standard naming scheme for each volume type. The hostPath volume types are named according to the path on the host machine, replacing forward slashes with hyphens less any leading and trailing forward slashes. The special case of the filesystem root, /, translates to the name root. Additionally, the name is suffixed with -host to avoid naming conflicts with persistentVolumeClaim volumes. Each persistentVolumeClaim volume type uses the name of its associated named volume suffixed with -pvc.

Note that if an init container is created with type once and the pod has been started, it does not show up in the generated kube YAML as once type init containers are deleted after they are run. If the pod has only been created and not started, it is in the generated kube YAML. Init containers created with type always are always generated in the kube YAML as they are never deleted, even after running to completion.

Note: When using volumes and generating a Kubernetes YAML for an unprivileged and rootless podman container on an SELinux enabled system, one of the following options must be completed:
* Add the "privileged: true" option to the pod spec
* Add type: spc_t under the securityContext seLinuxOptions in the pod spec
* Relabel the volume via the CLI command chcon -t container_file_t -R <directory>

Once completed, the correct permissions are in place to access the volume when the pod/container is created in a Kubernetes cluster.

Note that the generated Kubernetes YAML file can be used to re-run the deployment via podman-play-kube(1).

Note that if the pod being generated was created with the --infra-name flag set, then the generated kube yaml will have the io.podman.annotations.infra.name set where the value is the name of the infra container set by the user.

Also note that both Deployment and DaemonSet can only have restartPolicy set to Always.

OPTIONS¶

EXAMPLES¶

Create Kubernetes Pod YAML for a container called some-mariadb.

$ sudo podman kube generate some-mariadb
# Save the output of this file and use kubectl create -f to import
# it into Kubernetes.
#
# Created with podman-0.11.2-dev
apiVersion: v1
kind: Pod
metadata:


  creationTimestamp: 2018-12-03T19:07:59Z


  labels:


    app: some-mariadb


  name: some-mariadb-libpod
spec:


  containers:


  - command:


    - docker-entrypoint.sh


    - mysqld


    env:


    - name: HOSTNAME


    - name: GOSU_VERSION


      value: "1.10"


    - name: GPG_KEYS


      value: "199369E5404BD5FC7D2FE43BCBCB082A1BB943DB \t177F4010FE56CA3336300305F1656F24C74CD1D8


        \t430BDF5C56E7C94E848EE60C1C4CBDCDCD2EFD2A \t4D1BB29D63D98E422B2113B19334A25F8507EFA5"


    - name: MARIADB_MAJOR


      value: "10.3"


    - name: MARIADB_VERSION


      value: 1:10.3.10+maria~bionic


    - name: MYSQL_ROOT_PASSWORD


      value: x


    image: quay.io/baude/demodb:latest


    name: some-mariadb


    ports:


    - containerPort: 3306


      hostPort: 36533


    tty: true

Create Kubernetes Deployment YAML with 3 replicas for a container called dep-ctr

$ podman kube generate --type deployment --replicas 3 dep-ct
r
# Save the output of this file and use kubectl create -f to import
# it into Kubernetes.
#
# Created with podman-4.5.0-dev
apiVersion: apps/v1
kind: Deployment
metadata:


  creationTimestamp: "2023-03-27T20:45:08Z"


  labels:


    app: dep-ctr-pod


  name: dep-ctr-pod-deployment
spec:


  replicas: 3


  selector:


    matchLabels:


      app: dep-ctr-pod


  template:


    metadata:


      annotations:


        io.podman.annotations.ulimit: nofile=524288:524288,nproc=127332:127332


      creationTimestamp: "2023-03-27T20:45:08Z"


      labels:


        app: dep-ctr-pod


      name: dep-ctr-pod


    spec:


      containers:


      - command:


        - top


        image: docker.io/library/alpine:latest


        name: dep-ctr

Create Kubernetes Pod YAML for a container with the directory /home/user/my-data on the host bind-mounted in the container to /volume.

$ podman kube generate my-container-with-bind-mounted-data
# Save the output of this file and use kubectl create -f to import
# it into Kubernetes.
#
# Created with podman-3.1.0-dev
apiVersion: v1
kind: Pod
metadata:


  creationTimestamp: "2021-03-18T16:26:08Z"


  labels:


    app: my-container-with-bind-mounted-data


  name: my-container-with-bind-mounted-data
spec:


  containers:


  - command:


    - /bin/sh


    image: docker.io/library/alpine:latest


    name: test-bind-mount


    volumeMounts:


    - mountPath: /volume


      name: home-user-my-data-host


  restartPolicy: Never


  volumes:


  - hostPath:


      path: /home/user/my-data


      type: Directory


    name: home-user-my-data-host

Create Kubernetes Pod YAML for a container with the named volume priceless-data mounted in the container at /volume.

$ podman kube generate my-container-using-priceless-data
# Save the output of this file and use kubectl create -f to import
# it into Kubernetes.
#
# Created with podman-3.1.0-dev
apiVersion: v1
kind: Pod
metadata:


  creationTimestamp: "2021-03-18T16:26:08Z"


  labels:


    app: my-container-using-priceless-data


  name: my-container-using-priceless-data
spec:


  containers:


  - command:


    - /bin/sh


    image: docker.io/library/alpine:latest


    name: test-bind-mount


    volumeMounts:


    - mountPath: /volume


      name: priceless-data-pvc


  restartPolicy: Never


  volumes:


  - name: priceless-data-pvc


    persistentVolumeClaim:


      claimName: priceless-data

Create Kubernetes Pod YAML for a pod called demoweb and include a service.

$ sudo podman kube generate -s demoweb
# Save the output of this file and use kubectl create -f to import
# it into Kubernetes.
#
# Created with podman-0.12.2-dev
apiVersion: v1
kind: Pod
metadata:


  creationTimestamp: 2018-12-18T15:16:06Z


  labels:


    app: demoweb


  name: demoweb-libpod
spec:


  containers:


  - command:


    - python3


    - /root/code/graph.py


    image: quay.io/baude/demoweb:latest


    name: practicalarchimedes


    tty: true


    workingDir: /root/code
---
apiVersion: v1
kind: Service
metadata:


  creationTimestamp: 2018-12-18T15:16:06Z


  labels:


    app: demoweb


  name: demoweb-libpod
spec:


  ports:


  - name: "8050"


    nodePort: 31269


    port: 8050


    targetPort: 0


  selector:


    app: demoweb


  type: NodePort
status:


  loadBalancer: {}

SEE ALSO¶

podman(1), podman-container(1), podman-pod(1), podman-kube-play(1), podman-kube-down(1)

HISTORY¶

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