The default container runtime for Kubernetes is Docker, but Kubernetes is also compatible with other container runtimes. In this article, we'll take a look at running Kubernetes with Containerd.
Containerd is an industry-standard container runtime that is popular for its simplicity and robustness. It is also used by other container orchestration platforms such as Docker Swarm and Apache Mesos.
To install Containerd, you can use a package manager such as apt or yum.
sudo apt install containerd
Once Containerd is installed, you need to configure Kubernetes to use it as the container runtime. To do this, you need to edit the /etc/kubernetes/manifests/kubelet.yaml
file and add the following line:
--container-runtime=containerd
You also need to edit the /etc/systemd/system/kubelet.service.d/10-kubelet.conf
file and add the following line:
Environment="KUBELET_EXTRA_ARGS=--container-runtime=containerd"
After making these changes, you need to restart the kubelet
service.
sudo systemctl restart kubelet
Now that Kubernetes is configured to use Containerd, let's create a container.
First, we need to create a file called container.json
with the following contents:
{
"id": "container1",
"runtime": "containerd",
"image": "nginx:latest"
}
Next, we need to create the container using the ctr
command.
sudo ctr create -f container.json
Now that we have created a container, let's run it.
First, we need to create a file called run.json
with the following contents:
{
"id": "container1",
"runtime": "containerd",
"image": "nginx:latest",
"command": ["nginx", "-g", "daemon off;"]
}
Next, we need to run the container using the ctr
command.
sudo ctr run -f run.json
To delete a container, we can use the ctr
command.
sudo ctr delete container1
In this article, we have looked at how to use Kubernetes with Containerd. We have also seen how to install Containerd, configure Kubernetes to use it, and how to create and run containers.