containerd VS calico

Containerd and nerdctl

Kubernetes on the backend used to utilize docker for much of its container runtime solutions. One of the modular features of Kubernetes is the ability to utilize a Container Runtime Interface or CRI. The problem was that Docker didn't really meet the spec properly and they had to maintain a shim to translate properly. Instead users could utilize the popular containerd or cri-o runtimes. These follow the Open Container Initiative or OCI's guidelines on container formats.

Container Engine: A runtime that executes and manages containers. Docker and containerd are popular container engines.

Multiple container runtimes are supported, like conatinerd, cri-o, or other CRI compliant runtimes.

This is a failed attempt to upstream part of containerd changes: https://github.com/containerd/containerd/pull/8789

Other part of containerd changes waits for gods-know-what: https://github.com/containerd/containerd/pull/9054

But I haven't gave up yet.

containerd is required by kubernetes to handle containers on its behalf. A big thanks to the HostAfrica blog for the information on setting containerd up for debain. So the containerd install will need to happen on both the WSL2 instance and the Raspberry Pis. For WSL2 you can just install containerd directly:

The context deadline exceeded: unknown is also in containerd, and is a known problem.

Get:1 https://download.docker.com/linux/ubuntu focal/stable amd64 containerd.io amd64 1.6.21-1 [28.3 MB]

Docker Desktop adds a bunch of stuff to simplify local development and that’s why it has a larger memory footprint. You don’t use that when deploying but something like https://containerd.io/.

wget -O calicoctl https://github.com/projectcalico/calico/releases/latest/download/calicoctl-linux-amd64 chmod +x calicoctl sudo mv calicoctl /usr/local/bin/

You could use Calico in Google Cloud GKE. Apart from the CNI, you can also use Calico for defining network policies. Feel free to join the Calico communities on slack and Github. You can visit the Project Calico slack community https://slack.projectcalico.org/ or GitHub https://github.com/projectcalico/calico

We use Calico and they view this as a paid feature. https://github.com/projectcalico/calico/issues/1035

In eBPF mode we had this one: https://github.com/projectcalico/calico/issues/7110, fixed in the upcoming v3.26.0 release.

Another thread discusses setting it up and whether the L2 with ipaddresspool is supported is here https://github.com/projectcalico/calico/issues/6789 but it seems it is not tested .

$ kubectl apply -k ./ --dry-run='client' error: accumulating resources: accumulation err='accumulating resources from 'https://github.com/projectcalico/calico/manifests/tigera-operator.yaml?ref=v3.24.4': URL is a git repository': '/tmp/kustomize-3674962985/manifests/tigera-operator.yaml' refers to file 'tigera-operator.yaml'; expecting directory

If you do kubectl get pods --all-namespaces will show all the pods in Pending state, that's because we don't have any network plugin configured with our Kubernetes cluster. I use Calico network plugin for this demo but you can use any Kubernetes network plugin of your choice as long it has ability to define host gateway routes.