oracular (1) podman-kube-generate.1.gz
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
--filename, -f=filename
Output to the given file instead of STDOUT. If the file already exists, kube generate refuses to replace
it and returns an error.
--podman-only
Add podman-only reserved annotations in generated YAML file (Cannot be used by Kubernetes)
--replicas, -r=replica count
The value to set replicas to when generating a Deployment kind. Note: this can only be set with the
option --type=deployment.
--service, -s
Generate a Kubernetes service object in addition to the Pods. Used to generate a Service specification
for the corresponding Pod output. In particular, if the object has portmap bindings, the service
specification includes a NodePort declaration to expose the service. A random port is assigned by Podman
in the specification.
--type, -t=pod | deployment | daemonset
The Kubernetes kind to generate in the YAML file. Currently, the only supported Kubernetes specifications
are Pod, Deployment and DaemonSet. By default, the Pod specification is generated.
EXAMPLES
Create Kubernetes Pod YAML for the specified container.
$ podman kube generate some-mariadb
# Save the output of this file and use kubectl create -f to import
# it into Kubernetes.
#
# Created with podman-4.8.2
# NOTE: If you generated this yaml from an unprivileged and rootless podman container on an SELinux
# enabled system, check the podman generate kube man page for steps to follow to ensure that your pod/container
# has the right permissions to access the volumes added.
---
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: "2024-01-09T02:24:55Z"
labels:
app: some-mariadb-pod
name: some-mariadb-pod
spec:
containers:
- args:
- mariadbd
env:
- name: MARIADB_ROOT_PASSWORD
value: x
image: docker.io/library/mariadb:10.11
name: some-mariadb
ports:
- containerPort: 3306
hostPort: 34891
volumeMounts:
- mountPath: /var/lib/mysql
name: mariadb_data-pvc
volumes:
- name: mariadb_data-pvc
persistentVolumeClaim:
claimName: mariadb_data
Create Kubernetes Deployment YAML with 3 replicas for the specified container.
$ 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 the specified container with the host directory /home/user/my-data bind-
mounted onto the container path /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 the specified container with named volume priceless-data mounted onto the
container path /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 the specified pod 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)
podman-kube-generate(1)