安装docker时，自己添加了国内的hub.docker.com镜像
[root@ce-docker ~]# systemctl restart docker
出现以下报错：
Job for docker.service failed because start of the service was attempted too often. See "systemctl status docker.service" and "journalctl -xe" for details.
To force a start use "systemctl reset-failed docker.service" followed by "systemctl start docker.service" again.
[root@ce-docker ~]# vim /etc/docker/daemon.json
[root@ce-docker ~]# mv /etc/docker/daemon.json /etc/docker/daemon.conf
[root@ce-docker ~]# systemctl start docker
这样就成功了
[root@ce-docker ~]# service status docker
The service command supports only basic LSB actions (start, stop, restart, try-restart, reload, force-reload, status). For other actions, please try to use systemctl.
[root@ce-docker ~]# systemctl status docker
● docker.service - Docker Application Container Engine
Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)
Active: active (running) since 三 2019-06-26 11:25:10 CST; 43s ago
Docs: https://docs.docker.com
Main PID: 33473 (dockerd)
Tasks: 8
Memory: 28.8M
CGroup: /system.slice/docker.service
└─33473 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.620816911+08:00" level=info ms...grpc
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.624774687+08:00" level=info ms...ay2"
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.627037017+08:00" level=info ms...nds"
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.627583030+08:00" level=info ms...rt."
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.705312061+08:00" level=info ms...ess"
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.735358787+08:00" level=info ms...ne."
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.842464352+08:00" level=info ms...09.6
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.842687809+08:00" level=info ms...ion"
6月 26 11:25:10 ce-docker systemd[1]: Started Docker Application Container Engine.
6月 26 11:25:10 ce-docker dockerd[33473]: time="2019-06-26T11:25:10.865343198+08:00" level=info ms...ock"
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