I got some concerns regarding to use of containerd as CRI runtime inside K8s clusters from 1.20 version (In AKS from 1.19.x)
I am about to upgrade my AKS cluster to 1.19.x, and I understand the trade-offs in this link announcemnent Don’t Panic: Kubernetes and Docker | Kubernetes. But is still confusing for me the idea to modify the nodes to use containerd runtime whether it is something that I would have to do or I don’t have to.
I am reading here more about it. Container runtimes | Kubernetes, but is not clear for me the following:
If I upgrade my cluster to a version which one has containerd as a runtime and not docker (using docker-shim) anymore,
making this upgrade … can I expect all my nodes have the containerd runtime automatically installed?
Does the upgrade will just remove docker as a container runtime and I have to install my suitable flavour runtime on my own over my nodes?
The thing is, my production cluster is just fetching a docker image which one was built and pushed outside the cluster operations, so if I upgrade to 1.19.x version having containerd as a runtime there, I cannot expect to have issues and or have to do some modifications regarding to use of containerd, since all images produced from docker build will work on akk CRI implementations according to this Dockershim Deprecation FAQ | Kubernetes