安装环境：
Centos7.5
从 2017 年 3 月开始 docker 在原来的基础上分为两个分支版本: Docker CE 和 Docker EE。
1）Docker CE 即社区免费版
2）Docker EE 即企业版，强调安全，但需付费使用。
本文介绍 Docker CE 的安装使用。
1）移除旧的版本
查询当前的Docker版本
$ docker -v
如果存在已安装的Docker，卸载
$ sudo yum remove docker \ docker-client \ docker-client-latest \ docker-common \ docker-latest \ docker-latest-logrotate \ docker-logrotate \ docker-selinux \ docker-engine-selinux \ docker-engine
注意：卸载后，/var/lib/docker/ 下内容（images, containers, volumes,networks）依然被保留。
执行示例：
[root@master devops]# sudo yum remove docker \ > docker-client \ > docker-client-latest \ > docker-common \ > docker-latest \ > docker-latest-logrotate \ > docker-logrotate \ > docker-selinux \ > docker-engine-selinux \ > docker-engine Loaded plugins: fastestmirror No Match for argument: docker No Match for argument: docker-client No Match for argument: docker-client-latest No Match for argument: docker-common No Match for argument: docker-latest No Match for argument: docker-latest-logrotate No Match for argument: docker-logrotate No Match for argument: docker-selinux No Match for argument: docker-engine-selinux No Match for argument: docker-engine No Packages marked for removal
备注：因为之前这台服务器未安装过docker，因此会提示找不到。
2）配置库
3.1）安装所需的软件包 yum-utils、device-mapper-persistent-data和 lvm2
$ sudo yum install -y yum-utils \ device-mapper-persistent-data \ lvm2
执行示例：
[root@master devops]# sudo yum install -y yum-utils device-mapper-persistent-data lvm2 Loaded plugins: fastestmirror Determining fastest mirrors Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=extras&infra=stock error was 12: Timeout on http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=extras&infra=stock: (28, 'Operation too slow. Less than 1000 bytes/sec transferred the last 30 seconds') * base: mirrors.huaweicloud.com * extras: mirror.bit.edu.cn * updates: mirror.bit.edu.cn base | 3.6 kB 00:00:00 bintray--sbt-rpm | 1.3 kB 00:00:00 http://mirrors.cn99.com/centos/7.5.1804/extras/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found Trying other mirror. mysql-connectors-community | 2.5 kB 00:00:00 mysql-tools-community | 2.5 kB 00:00:00 mysql57-community | 2.5 kB 00:00:00 updates | 3.4 kB 00:00:00 (1/7): base/7/x86_64/group_gz | 166 kB 00:00:00 (2/7): mysql-tools-community/x86_64/primary_db | 61 kB 00:00:01 (3/7): bintray--sbt-rpm/primary | 4.2 kB 00:00:01 (4/7): mysql-connectors-community/x86_64/primary_db | 44 kB 00:00:02 (5/7): mysql57-community/x86_64/primary_db | 184 kB 00:00:01 (6/7): base/7/x86_64/primary_db | 6.0 MB 00:00:05 (7/7): updates/7/x86_64/primary_db | 7.4 MB 00:00:05 bintray--sbt-rpm 37/37 Package device-mapper-persistent-data-0.7.3-3.el7.x86_64 already installed and latest version Resolving Dependencies --> Running transaction check ---> Package lvm2.x86_64 7:2.02.177-4.el7 will be updated ---> Package lvm2.x86_64 7:2.02.180-10.el7_6.8 will be an update --> Processing Dependency: lvm2-libs = 7:2.02.180-10.el7_6.8 for package: 7:lvm2-2.02.180-10.el7_6.8.x86_64 ---> Package yum-utils.noarch 0:1.1.31-50.el7 will be installed --> Processing Dependency: python-kitchen for package: yum-utils-1.1.31-50.el7.noarch --> Processing Dependency: libxml2-python for package: yum-utils-1.1.31-50.el7.noarch --> Running transaction check ---> Package libxml2-python.x86_64 0:2.9.1-6.el7_2.3 will be installed ---> Package lvm2-libs.x86_64 7:2.02.177-4.el7 will be updated ---> Package lvm2-libs.x86_64 7:2.02.180-10.el7_6.8 will be an update --> Processing Dependency: device-mapper-event = 7:1.02.149-10.el7_6.8 for package: 7:lvm2-libs-2.02.180-10.el7_6.8.x86_64 ---> Package python-kitchen.noarch 0:1.1.1-5.el7 will be installed --> Processing Dependency: python-chardet for package: python-kitchen-1.1.1-5.el7.noarch --> Running transaction check ---> Package device-mapper-event.x86_64 7:1.02.146-4.el7 will be updated ---> Package device-mapper-event.x86_64 7:1.02.149-10.el7_6.8 will be an update --> Processing Dependency: device-mapper-event-libs = 7:1.02.149-10.el7_6.8 for package: 7:device-mapper-event-1.02.149-10.el7_6.8.x86_64 --> Processing Dependency: device-mapper = 7:1.02.149-10.el7_6.8 for package: 7:device-mapper-event-1.02.149-10.el7_6.8.x86_64 ---> Package python-chardet.noarch 0:2.2.1-1.el7_1 will be installed --> Running transaction check ---> Package device-mapper.x86_64 7:1.02.146-4.el7 will be updated --> Processing Dependency: device-mapper = 7:1.02.146-4.el7 for package: 7:device-mapper-libs-1.02.146-4.el7.x86_64 ---> Package device-mapper.x86_64 7:1.02.149-10.el7_6.8 will be an update ---> Package device-mapper-event-libs.x86_64 7:1.02.146-4.el7 will be updated ---> Package device-mapper-event-libs.x86_64 7:1.02.149-10.el7_6.8 will be an update --> Running transaction check ---> Package device-mapper-libs.x86_64 7:1.02.146-4.el7 will be updated ---> Package device-mapper-libs.x86_64 7:1.02.149-10.el7_6.8 will be an update --> Finished Dependency Resolution Dependencies Resolved ======================================================================================== Package Arch Version Repository Size ======================================================================================== Installing: yum-utils noarch 1.1.31-50.el7 base 121 k Updating: lvm2 x86_64 7:2.02.180-10.el7_6.8 updates 1.3 M Installing for dependencies: libxml2-python x86_64 2.9.1-6.el7_2.3 base 247 k python-chardet noarch 2.2.1-1.el7_1 base 227 k python-kitchen noarch 1.1.1-5.el7 base 267 k Updating for dependencies: device-mapper x86_64 7:1.02.149-10.el7_6.8 updates 293 k device-mapper-event x86_64 7:1.02.149-10.el7_6.8 updates 189 k device-mapper-event-libs x86_64 7:1.02.149-10.el7_6.8 updates 188 k device-mapper-libs x86_64 7:1.02.149-10.el7_6.8 updates 321 k lvm2-libs x86_64 7:2.02.180-10.el7_6.8 updates 1.1 M Transaction Summary ======================================================================================== Install 1 Package (+3 Dependent packages) Upgrade 1 Package (+5 Dependent packages) Total download size: 4.2 M Downloading packages: Delta RPMs disabled because /usr/bin/applydeltarpm not installed. (1/10): device-mapper-1.02.149-10.el7_6.8.x86_64.rpm | 293 kB 00:00:00 (2/10): libxml2-python-2.9.1-6.el7_2.3.x86_64.rpm | 247 kB 00:00:01 (3/10): device-mapper-event-libs-1.02.149-10.el7_6.8.x86_64.rpm | 188 kB 00:00:01 (4/10): device-mapper-event-1.02.149-10.el7_6.8.x86_64.rpm | 189 kB 00:00:01 (5/10): python-chardet-2.2.1-1.el7_1.noarch.rpm | 227 kB 00:00:00 (6/10): device-mapper-libs-1.02.149-10.el7_6.8.x86_64.rpm | 321 kB 00:00:01 (7/10): yum-utils-1.1.31-50.el7.noarch.rpm | 121 kB 00:00:01 (8/10): lvm2-libs-2.02.180-10.el7_6.8.x86_64.rpm | 1.1 MB 00:00:01 (9/10): python-kitchen-1.1.1-5.el7.noarch.rpm | 267 kB 00:00:01 (10/10): lvm2-2.02.180-10.el7_6.8.x86_64.rpm | 1.3 MB 00:00:03 --------------------------------------------------------------------------------------- Total 979 kB/s | 4.2 MB 00:00:04 Running transaction check Running transaction test Transaction test succeeded Running transaction Updating : 7:device-mapper-1.02.149-10.el7_6.8.x86_64 1/16 Updating : 7:device-mapper-libs-1.02.149-10.el7_6.8.x86_64 2/16 Updating : 7:device-mapper-event-libs-1.02.149-10.el7_6.8.x86_64 3/16 Updating : 7:device-mapper-event-1.02.149-10.el7_6.8.x86_64 4/16 Updating : 7:lvm2-libs-2.02.180-10.el7_6.8.x86_64 5/16 Installing : python-chardet-2.2.1-1.el7_1.noarch 6/16 Installing : python-kitchen-1.1.1-5.el7.noarch 7/16 Installing : libxml2-python-2.9.1-6.el7_2.3.x86_64 8/16 Installing : yum-utils-1.1.31-50.el7.noarch 9/16 Updating : 7:lvm2-2.02.180-10.el7_6.8.x86_64 10/16 Cleanup : 7:lvm2-2.02.177-4.el7.x86_64 11/16 Cleanup : 7:lvm2-libs-2.02.177-4.el7.x86_64 12/16 Cleanup : 7:device-mapper-event-1.02.146-4.el7.x86_64 13/16 Cleanup : 7:device-mapper-event-libs-1.02.146-4.el7.x86_64 14/16 Cleanup : 7:device-mapper-1.02.146-4.el7.x86_64 15/16 Cleanup : 7:device-mapper-libs-1.02.146-4.el7.x86_64 16/16 Verifying : 7:device-mapper-event-1.02.149-10.el7_6.8.x86_64 1/16 Verifying : 7:device-mapper-libs-1.02.149-10.el7_6.8.x86_64 2/16 Verifying : yum-utils-1.1.31-50.el7.noarch 3/16 Verifying : libxml2-python-2.9.1-6.el7_2.3.x86_64 4/16 Verifying : python-chardet-2.2.1-1.el7_1.noarch 5/16 Verifying : 7:device-mapper-event-libs-1.02.149-10.el7_6.8.x86_64 6/16 Verifying : python-kitchen-1.1.1-5.el7.noarch 7/16 Verifying : 7:lvm2-2.02.180-10.el7_6.8.x86_64 8/16 Verifying : 7:lvm2-libs-2.02.180-10.el7_6.8.x86_64 9/16 Verifying : 7:device-mapper-1.02.149-10.el7_6.8.x86_64 10/16 Verifying : 7:device-mapper-event-libs-1.02.146-4.el7.x86_64 11/16 Verifying : 7:device-mapper-1.02.146-4.el7.x86_64 12/16 Verifying : 7:device-mapper-event-1.02.146-4.el7.x86_64 13/16 Verifying : 7:lvm2-libs-2.02.177-4.el7.x86_64 14/16 Verifying : 7:lvm2-2.02.177-4.el7.x86_64 15/16 Verifying : 7:device-mapper-libs-1.02.146-4.el7.x86_64 16/16 Installed: yum-utils.noarch 0:1.1.31-50.el7 Dependency Installed: libxml2-python.x86_64 0:2.9.1-6.el7_2.3 python-chardet.noarch 0:2.2.1-1.el7_1 python-kitchen.noarch 0:1.1.1-5.el7 Updated: lvm2.x86_64 7:2.02.180-10.el7_6.8 Dependency Updated: device-mapper.x86_64 7:1.02.149-10.el7_6.8 device-mapper-event.x86_64 7:1.02.149-10.el7_6.8 device-mapper-event-libs.x86_64 7:1.02.149-10.el7_6.8 device-mapper-libs.x86_64 7:1.02.149-10.el7_6.8 lvm2-libs.x86_64 7:2.02.180-10.el7_6.8 Complete!