Containerd is the recommended CRI (Container Runtime Interface). If docker was previously installed and containerd is enabled in the yaml spec, then the cluster will be migrated to containerd and docker will be uninstalled.
As CentOS, RHEL and Oracle Linux 8.x do not support Docker, the Containerd CRI is required.
Containerd 1.4.8+ has dropped support for Ubuntu 16.04.
spec: containerd: version: 1.4.6 preserveConfig: false tomlConfig: | [debug] "level" = "info"
|version||The version of containerd to be installed|
|tomlConfig||Containerd config settings that will be merged into /etc/containerd/config.toml|
|preserveConfig||This flag will ensure that nothing is changed in the existing containerd config on the system, regardless of other options.|