问题现象：

[root@qianyi-ecs ~]# docker login --username=xxxx cr.registry.res.xxxx.cloud
Password:
Error response from daemon: Get "https://xx.xx.xx.xx": x509: certificate signed by unknown authority

 自守护进程的错误响应：Gethttps://xx.xx.xx.xx: x509:由未知权限签署的证书。

解决办法：检查守护进程（docker）的配置

[root@qianyi-node1 ~]# vim /etc/docker/daemon.json
[root@qianyi-node1 ~]#
[root@qianyi-node1 ~]# cat /etc/docker/daemon.json
{
    "registry-mirrors": [
         "https://cr.registry.res.xxxx.cloud"
    ],
    "insecure-registries":[
        "cr.registry.res.xxxx.cloud"
    ]
}

[root@qianyi-node1 ~]# service docker restart
Redirecting to /bin/systemctl restart docker.service
[root@qianyi-node1 ~]#
[root@qianyi-node1 ~]# docker login --username=xxxx cr.registry.res.xxx.cloud
Password:
WARNING! Your password will be stored unencrypted in /root/.docker/config.json.
Configure a credential helper to remove this warning. See
https://docs.docker.com/engine/reference/commandline/login/#credentials-store

Login Succeeded
[root@qianyi-node1 ~]#