Virtual Kubelet Podman Provider - Beta

Virtual Kubelet Provider implementation to manages containers in podman environments.

Important: Project is under development and currently only basic functionality is available

Purpose

The whole point of the Virtual Kubelet project is to provide an interface for container runtimes that don't conform to the standard node-based model. The Kubelet codebase is the comprehensive standard CRI node agent and this Provider is not attempting to recreate that.

Dependencies

Podman must be installed on the provider node. Podman provider uses varlink podman API to communicate. This must be enabled for podman provider to work.

Running

Production

To run podman provider in production configuration requires minimal configuration

# create vkubelet and kubernetes directories
mkdir -p /etc/kubernetes/ /etc/vkubelet/
# copy kubeconfig into kubernetes directory
cp $KUBECONFIG /etc/kubernetes/admin.conf
# Copy systemd file into the destination node.
cp ./deploy/systemd/vkubelet-podman.service /usr/lib/systemd/system/vkubelet-podman.service
# Copy vkubelet configuration file. Modify it based on your requirments
cp ./deploy/systemd/podman-cfg.json /etc/vkubelet/podman-cfg.json
# Copy vkubelet binary
cp ./bin/virtual-kubelet .usr/local/bin/virtual-kubelet
# Reload and start vkubelet daemon
systemctl daemon-reload
systemctl start vkubelet-podman
systemctl status vkubelet-podman

Development

For local development it is easiest way to iterate is to use use [minikube](https://github.com/kubernetes/minikube)

#start minikube
minikube start

#start varlink podman socket
systemctl start io.podman.service

# start provider
make run
kubectl create -f deploy/example/pod-example.yaml
# you should see pod running in podman (you might need root to check it)
podman ps

Limitations

• Only hostPath volume provider is supported
• Only one container per pod is supported
• No Secrets or ConfigMaps is supported yet

Podman install & configuration

yum distro-sync --enablerepo=updates-testing install podman containers-common sudo
systemctl enable --now io.podman.socket
systemctl status io.podman.socket

I have enabled my local dev user to access socket for development:

[Socket]
ListenStream=/run/podman/io.podman
SocketMode=0770
SocketGroup=root
SocketUser=$USER

vi /etc/tmpfiles.d/podman.conf:

d /run/podman 0770 root $USER

Roadmap

Provider Roadmap