启动docker报错
[root@ opt]# systemctl status docker.service -l
● docker.service - Docker Application Container Engine
Loaded: loaded (/usr/lib/systemd/system/docker.service; disabled; vendor preset: disabled)
Active: activating (start) since 二 2017-11-07 16:46:51 CST; 9s ago
Docs: http://docs.docker.com
▽Main PID: 8856 (docker-current)
Memory: 341.8M
CGroup: /system.slice/docker.service
└─8856 /usr/bin/docker-current daemon --exec-opt native.cgroupdriver=systemd --selinux-enabled --ip=10.2.0.6 -b=docker0 --insecure-registry=10.2.0.6:5000
11月 07 16:46:51 systemd[1]: Starting Docker Application Container Engine...
11月 07 16:46:59 docker-current[8856]: time="2017-11-07T16:46:59.653934630+08:00" level=warning msg="devmapper: Usage of loopback devices is strongly discouraged for production use. Please use `--storage-opt dm.thinpooldev` or use `man docker` to refer to dm.thinpooldev section."
11月 07 16:46:59 docker-current[8856]: time="2017-11-07T16:46:59.868187155+08:00" level=warning msg="devmapper: Base device already exists and has
filesystem xfs on it. User specified filesystem will be ignored."
11月 07 16:46:59 docker-current[8856]: time="2017-11-07T16:46:59.886541240+08:00" level=info msg="[graphdriver] using prior storage driver \"devicemapper\""
临时解决方案：
vim /etc/sysconfig/docker
DOCKER_STORAGE_OPTIONS="--storage-opt dm.no_warn_on_loop_devices=true"
