默认情况下，Docker只允许通过unix socket通信操作Docker daemon，但有时我们想通过HTTP调用其Rest API，需单独配置启动参数。
为了使配置永久生效，在Ubuntu环境下修改其配置文件/etc/default/docker，加入DOCKER_OPTS="-H=unix:///var/run/docker.sock -H=0.0.0.0:6732"，重启Docker服务，可通过浏览器访问设置主机：端口号（6372）/ Docker API操作Docker，后续会补充基于API如何做一个简单的管理工具，先来一张雏形图。
# Docker Upstart and SysVinit configuration file
# Customize location of Docker binary (especially for development testing).
#DOCKER="/usr/local/bin/docker"
# Use DOCKER_OPTS to modify the daemon startup options.
#DOCKER_OPTS="--dns 8.8.8.8 --dns 8.8.4.4"
DOCKER_OPTS="-H=unix:///var/run/docker.sock -H=0.0.0.0:6732"
# If you need Docker to use an HTTP proxy, it can also be specified here.
#export http_proxy="http://127.0.0.1:3128/"
# This is also a handy place to tweak where Docker's temporary files go.
#export TMPDIR="/mnt/bigdrive/docker-tmp"
