Containerd

An open and reliable Containers runtime.

Containerd create a system where content (images) is stored in the machine for executing containers. Default folder in Linux is var/lib/containerd/io.containerd.content.v1.content, this flow is described here.

Crtctl

crictl ⇒ Commands or the same as Docker commands.

# show images
crictl images
# show containers running
crictl ps
# display containerd information 
crictl info
# prune images
crictl rmi --prune

systemctl restart containerd

• How to add Insecure Registry:

# /etc/containerd/config.toml
# change <IP>:5000 to your registry url
 
[plugins."io.containerd.grpc.v1.cri".registry]
  [plugins."io.containerd.grpc.v1.cri".registry.mirrors]
    [plugins."io.containerd.grpc.v1.cri".registry.mirrors."<IP>:5000"]
      endpoint = ["http://<IP>:5000"]
  [plugins."io.containerd.grpc.v1.cri".registry.configs]
    [plugins."io.containerd.grpc.v1.cri".registry.configs."<IP>:5000".tls]
      insecure_skip_verify = true

Nerdctl

Install nerdctl.

export NERDCTL_VERSION=1.2.0 # see https://github.com/containerd/nerdctl/releases for the latest release
 
wget -q "https://github.com/containerd/nerdctl/releases/download/v${NERDCTL_VERSION}/nerdctl-${NERDCTL_VERSION}-linux-amd64.tar.gz" -O /tmp/nerdctl.tar.gz
mkdir -p ~/.local/bin
tar -C ~/.local/bin/ -xzf /tmp/nerdctl.tar.gz
# or
sudo tar -C /usr/local/bin/ -xzf /tmp/nerdctl.tar.gz

# show kubernetes containers running
nerdctl -n k8s.io ps
# show docker containers running
nerdctl -n movy ps