操作环境：

CentOS7操作系统

Docker

一、修改配置文件

配置文件位置：/etc/sysconfig/docker

添加红色语句

# /etc/sysconfig/docker

# Modify these options if you want to change the way the docker daemon runs
OPTIONS='--selinux-enabled --log-driver=journald --signature-verification=false'
if [ -z "${DOCKER_CERT_PATH}" ]; then
    DOCKER_CERT_PATH=/etc/docker
fi

DOCKER_OPTS="-H unix:///var/run/docker.sock -H 0.0.0.0:2376"
# If you want to add your own registry to be used for docker search and docker
# pull use the ADD_REGISTRY option to list a set of registries, each prepended
# with --add-registry flag. The first registry added will be the first registry
# searched.
# ADD_REGISTRY='--add-registry registry.access.redhat.com'

# If you want to block registries from being used, uncomment the BLOCK_REGISTRY
# option and give it a set of registries, each prepended with --block-registry
# flag. For example adding docker.io will stop users from downloading images
# from docker.io
# BLOCK_REGISTRY='--block-registry'

# If you have a registry secured with https but do not have proper certs
# distributed, you can tell docker to not look for full authorization by
# adding the registry to the INSECURE_REGISTRY line and uncommenting it.
# INSECURE_REGISTRY='--insecure-registry'

# On an SELinux system, if you remove the --selinux-enabled option, you
# also need to turn on the docker_transition_unconfined boolean.
# setsebool -P docker_transition_unconfined 1

# Location used for temporary files, such as those created by
# docker load and build operations. Default is /var/lib/docker/tmp
# Can be overriden by setting the following environment variable.
# DOCKER_TMPDIR=/var/tmp

# Controls the /etc/cron.daily/docker-logrotate cron job status.
# To disable, uncomment the line below.
# LOGROTATE=false
#

# docker-latest daemon can be used by starting the docker-latest unitfile.
# To use docker-latest client, uncomment below lines
#DOCKERBINARY=/usr/bin/docker-latest
#DOCKERDBINARY=/usr/bin/dockerd-latest
#DOCKER_CONTAINERD_BINARY=/usr/bin/docker-containerd-latest
#DOCKER_CONTAINERD_SHIM_BINARY=/usr/bin/docker-containerd-shim-latest

二、引用配置文件

Docker的启动命令：systemctl start docker.service（注意systemctl在CentOS6.5或以下的版本中不存在）

所以我们要找到启动文件docker.service（/lib/systemd/system/docker.service）

添加红色的语句

[Unit]
Description=Docker Application Container Engine
Documentation=http://docs.docker.com
After=network.target
Wants=docker-storage-setup.service
Requires=docker-cleanup.timer

[Service]
Type=notify
NotifyAccess=all
EnvironmentFile=-/etc/sysconfig/docker
EnvironmentFile=-/etc/sysconfig/docker-storage
EnvironmentFile=-/etc/sysconfig/docker-network
Environment=GOTRACEBACK=crash
Environment=DOCKER_HTTP_HOST_COMPAT=1
Environment=PATH=/usr/libexec/docker:/usr/bin:/usr/sbin
ExecStart=/usr/bin/dockerd-current\
          --add-runtime docker-runc=/usr/libexec/docker/docker-runc-current \
          --default-runtime=docker-runc \
          --exec-opt native.cgroupdriver=systemd \
          --userland-proxy-path=/usr/libexec/docker/docker-proxy-current \
          $OPTIONS \
          $DOCKER_STORAGE_OPTIONS \
          $DOCKER_NETWORK_OPTIONS \
          $ADD_REGISTRY \
          $BLOCK_REGISTRY \
          $INSECURE_REGISTRY\
          $DOCKER_OPTS
ExecReload=/bin/kill -s HUP $MAINPID
LimitNOFILE=1048576
LimitNPROC=1048576
LimitCORE=infinity
TimeoutStartSec=0
Restart=on-abnormal
MountFlags=slave

[Install]
WantedBy=multi-user.target

注意：

• Environment参数：引用文件（这里不需要引用，因为他已经引用了/etc/sysconfig/docker,如果没引用，那么第一步的操作没意义）
• ExecStart参数：启动时的配置（$DOCKER_OPTS引用这个参数，如果没引用，那么第一步的操作同样没意义）
• ExecStart中每一个参数之间必须有"\"，没有启动会报错
• 如果防火墙开启，则需要开启2376端口，或关闭防火墙

docker -H 192.168.1.1:2376 images