启动docker时报如下错误，一时间无从下手，然后更新源，又遇到一堆依赖无法解决的错误，最后加上--force, --nodeps更新源，期间因为其他任务而暂时将这个搁置，隔了几天后，重新折腾docker，将docker卸载，重新安装，启动，居然好了，呵呵，也许是依赖问题吧。
[root@localhost /]# systemctl start docker.service
Job for docker.service failed. See 'systemctl status docker.service' and 'journalctl -xn' for details.
[root@localhost /]# systemctl status docker.service
docker.service - Docker Application Container Engine
Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled)
Active: failed (Result: start-limit) since Thu 2014-11-27 15:03:24 CST; 13s ago
Docs: http://docs.docker.io
Process: 4559 ExecStart=/usr/bin/docker -d $OPTIONS $DOCKER_STORAGE_OPTIONS (code=exited, status=1/FAILURE)
Main PID: 4559 (code=exited, status=1/FAILURE)
Nov 27 15:03:24 localhost.localdomain systemd[1]: docker.service: main proces...
Nov 27 15:03:24 localhost.localdomain systemd[1]: Failed to start Docker Appl...
Nov 27 15:03:24 localhost.localdomain systemd[1]: Unit docker.service entered...
Nov 27 15:03:24 localhost.localdomain systemd[1]: docker.service holdoff time...
Nov 27 15:03:24 localhost.localdomain systemd[1]: Stopping Docker Application...
Nov 27 15:03:24 localhost.localdomain systemd[1]: Starting Docker Application...
Nov 27 15:03:24 localhost.localdomain systemd[1]: docker.service start reques...
Nov 27 15:03:24 localhost.localdomain systemd[1]: Failed to start Docker Appl...
Nov 27 15:03:24 localhost.localdomain systemd[1]: Unit docker.service entered...
Hint: Some lines were ellipsized, use -l to show in full.