TL; DR

root@tencent-sh1:~# cat /etc/rancher/k3s/registries.yaml 
mirrors:
  "docker.io":
    endpoint:
      - "https://harbor.xxx.me"
    rewrite:
      "^(.*)": "mirror-dockerhub/$1"
  "registry.k8s.io":
    endpoint:
      - "https://harbor.xxx.me"
    rewrite:
      "^(.*)": "mirror-registry-k8s-io/$1"
  "ghcr.io":
    endpoint:
      - "https://harbor.xxx.me"
    rewrite:
      "^(.*)": "mirror-registry-ghcr-io/$1"
  "quay.io":
    endpoint:
      - "https://harbor.xxx.me"
    rewrite:
      "^(.*)": "mirror-registry-quay-io/$1"

以上是我的配置，在 harbor 中镜像以上镜像源，之后这样 配置即可。

如果没有路径，比如使用 registry 镜像，忽略 rewrite 部分即可。