centos7 docker容器启动报错

centos7 运行
systemctl start docker.service

出现如下错误

Job for docker.service failed because the control process exited with error code. See "systemctl status docker.service" and "journal              ctl -xe" for details
运行 journalctl -xe 查看日志信息

unable to configure the Docker daemon with file /etc/docker/daemon.js
12月 25 16:23:39 localhost.localdomain systemd[1]: docker.service: main process exited, code=exited, status=1/FAILURE
12月 25 16:23:39 localhost.localdomain systemd[1]: Failed to start Docker Application Container Engine.
-- Subject: Unit docker.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit docker.service has failed.
--
-- The result is failed.
12月 25 16:23:39 localhost.localdomain systemd[1]: Unit docker.service entered failed state.
12月 25 16:23:39 localhost.localdomain systemd[1]: docker.service failed.
12月 25 16:23:39 localhost.localdomain polkitd[8554]: Unregistered Authentication Agent for unix-process:84471:192413129 (system bus
 ESCOC
 Storage Setup...
devel
Storage Setup.
p
devel
 Application Container Engine...
devel
ble to configure the Docker daemon with file /etc/docker/daemon.json: invalid character '}' looking for beginning of object key stri
 main process exited, code=exited, status=1/FAILURE
 Docker Application Container Engine

查看docker的版本

docker --version

运行
docker info

查看daemon.json文件

cd /etc/docker/
vi daemon.json
将doaemon.json文件中的","号删除，然后保存
启动docker 服务
systemctl start docker.service