containerd Mirroring From zot¶

containerd supports registry mirroring and zot can be used as an upstream registry to mirror from.

If your images are in a repository named docker in the zot registry and you want containerd to pull and mirror images from this repository, then your containerd configuration would look like the following.

containerd v1.x¶

The registry mirror configuration is specified inline as the plugin.

version = 2

[plugins."io.containerd.grpc.v1.cri".registry.mirrors."docker.io"]
endpoint = ['https://<my zot instance>:8080/v2/docker']

Note that /v2 is required for this to work.

containerd v2.x¶

The registry mirror configuration has changed in v2.x and now follows a directory structure. The following example shows how zot can be used as the default mirror registry.

version = 3

[plugins."io.containerd.cri.v1.images".registry]
  config_path = "/etc/containerd/certs.d"

$ tree /etc/containerd/certs.d

/etc/containerd/certs.d/
└── _default
    └── hosts.toml

$ cat /etc/containerd/certs.d/_default/hosts.toml

# zot is running at localhost:8080
server = "http://localhost:8080"

More information about various mirror registry configuration options is available here.