当从私有镜像库拉取镜像时出现如下问题：
docker pull myregistry:xx
Error response from daemon: Get https://xxx:5000/v1/_ping: http: server gave HTTP response to HTTPS client
解决方法：
修改该或者新建/etc/docker/daemon.json
添加下面这条语句：
{ "insecure-registries":["myregistry.example.com:5000"] }
然后重启docker服务：
sudo service docker restart
解决。
参考：https://github.com/docker/distribution/issues/1874
docker version
Client:
Version: 1.12.1
API version: 1.24
Go version: go1.6.2
Git commit: 23cf638
Built: Tue, 27 Sep 2016 12:25:38 +1300
OS/Arch: linux/ppc64le
Server:
Version: 1.12.1
API version: 1.24
Go version: go1.6.2
Git commit: 23cf638
Built: Tue, 27 Sep 2016 12:25:38 +1300
OS/Arch: linux/ppc64le
