适用于RHEL/CentOS 7的 rpm 包下载地址：
Index of linux/centos/7/x86_64/stable/Packages/ (docker.com)https://download.docker.com/linux/centos/7/x86_64/stable/Packages/ 官方需要下载的包共计 5 个，如下所示：
下载完成后，将上面的包上传到CentOS7.9系统中，然后离线下载所需的其它依赖包，依赖包的下载数量与系统安装的模式有关，如：GUI模式和最小化模式，所需的依赖包数量是不一样的。
[root@docker-ce docker-ce-20.10.9]# yum install *.rpm --downloadonly --downloaddir=./ Loaded plugins: fastestmirror, langpacks Examining containerd.io-1.4.9-3.1.el7.x86_64.rpm: containerd.io-1.4.9-3.1.el7.x86_64 Marking containerd.io-1.4.9-3.1.el7.x86_64.rpm to be installed Examining docker-ce-20.10.9-3.el7.x86_64.rpm: 3:docker-ce-20.10.9-3.el7.x86_64 Marking docker-ce-20.10.9-3.el7.x86_64.rpm to be installed Examining docker-ce-cli-20.10.9-3.el7.x86_64.rpm: 1:docker-ce-cli-20.10.9-3.el7.x86_64 Marking docker-ce-cli-20.10.9-3.el7.x86_64.rpm to be installed Examining docker-ce-rootless-extras-20.10.9-3.el7.x86_64.rpm: docker-ce-rootless-extras-20.10.9-3.el7.x86_64 Marking docker-ce-rootless-extras-20.10.9-3.el7.x86_64.rpm to be installed Examining docker-scan-plugin-0.8.0-3.el7.x86_64.rpm: docker-scan-plugin-0.8.0-3.el7.x86_64 Marking docker-scan-plugin-0.8.0-3.el7.x86_64.rpm to be installed Resolving Dependencies --> Running transaction check ---> Package containerd.io.x86_64 0:1.4.9-3.1.el7 will be installed --> Processing Dependency: container-selinux >= 2:2.74 for package: containerd.io-1.4.9-3.1.el7.x86_64 Determining fastest mirrors * base: mirrors.ustc.edu.cn * extras: mirrors.ustc.edu.cn * updates: mirrors.ustc.edu.cn base | 3.6 kB 00:00:00 extras | 2.9 kB 00:00:00 updates | 2.9 kB 00:00:00 (1/4): base/7/x86_64/group_gz | 153 kB 00:00:00 (2/4): extras/7/x86_64/primary_db | 243 kB 00:00:00 (3/4): base/7/x86_64/primary_db | 6.1 MB 00:00:02 (4/4): updates/7/x86_64/primary_db | 11 MB 00:00:02 ---> Package docker-ce.x86_64 3:20.10.9-3.el7 will be installed ---> Package docker-ce-cli.x86_64 1:20.10.9-3.el7 will be installed ---> Package docker-ce-rootless-extras.x86_64 0:20.10.9-3.el7 will be installed --> Processing Dependency: fuse-overlayfs >= 0.7 for package: docker-ce-rootless-extras-20.10.9-3.el7.x86_64 --> Processing Dependency: slirp4netns >= 0.4 for package: docker-ce-rootless-extras-20.10.9-3.el7.x86_64 ---> Package docker-scan-plugin.x86_64 0:0.8.0-3.el7 will be installed --> Running transaction check ---> Package container-selinux.noarch 2:2.119.2-1.911c772.el7_8 will be installed ---> Package fuse-overlayfs.x86_64 0:0.7.2-6.el7_8 will be installed --> Processing Dependency: libfuse3.so.3(FUSE_3.2)(64bit) for package: fuse-overlayfs-0.7.2-6.el7_8.x86_64 --> Processing Dependency: libfuse3.so.3(FUSE_3.0)(64bit) for package: fuse-overlayfs-0.7.2-6.el7_8.x86_64 --> Processing Dependency: libfuse3.so.3()(64bit) for package: fuse-overlayfs-0.7.2-6.el7_8.x86_64 ---> Package slirp4netns.x86_64 0:0.4.3-4.el7_8 will be installed --> Running transaction check ---> Package fuse3-libs.x86_64 0:3.6.1-4.el7 will be installed --> Finished Dependency Resolution Dependencies Resolved ================================================================================================================================================================================================================== Package Arch Version Repository Size ================================================================================================================================================================================================================== Installing: containerd.io x86_64 1.4.9-3.1.el7 /containerd.io-1.4.9-3.1.el7.x86_64 112 M docker-ce x86_64 3:20.10.9-3.el7 /docker-ce-20.10.9-3.el7.x86_64 96 M docker-ce-cli x86_64 1:20.10.9-3.el7 /docker-ce-cli-20.10.9-3.el7.x86_64 139 M docker-ce-rootless-extras x86_64 20.10.9-3.el7 /docker-ce-rootless-extras-20.10.9-3.el7.x86_64 19 M docker-scan-plugin x86_64 0.8.0-3.el7 /docker-scan-plugin-0.8.0-3.el7.x86_64 13 M Installing for dependencies: container-selinux noarch 2:2.119.2-1.911c772.el7_8 extras 40 k fuse-overlayfs x86_64 0.7.2-6.el7_8 extras 54 k fuse3-libs x86_64 3.6.1-4.el7 extras 82 k slirp4netns x86_64 0.4.3-4.el7_8 extras 81 k Transaction Summary ================================================================================================================================================================================================================== Install 5 Packages (+4 Dependent packages) Total size: 380 M Total download size: 258 k Installed size: 381 M Background downloading packages, then exiting: warning: /root/docker-ce-20.10.9/container-selinux-2.119.2-1.911c772.el7_8.noarch.rpm: Header V3 RSA/SHA256 Signature, key ID f4a80eb5: NOKEY Public key for container-selinux-2.119.2-1.911c772.el7_8.noarch.rpm is not installed (1/4): container-selinux-2.119.2-1.911c772.el7_8.noarch.rpm | 40 kB 00:00:00 (2/4): fuse-overlayfs-0.7.2-6.el7_8.x86_64.rpm | 54 kB 00:00:00 (3/4): fuse3-libs-3.6.1-4.el7.x86_64.rpm | 82 kB 00:00:00 (4/4): slirp4netns-0.4.3-4.el7_8.x86_64.rpm | 81 kB 00:00:00 ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Total 1.5 MB/s | 258 kB 00:00:00 exiting because "Download Only" specified
下载完依赖包，可以发现我这个系统安装docker-ce所需的包数量为 9 个。
[root@docker-ce docker-ce-20.10.9]# ls -ltr
total 96652
-rw-r--r-- 1 root root 55796 Apr 28 2020 fuse-overlayfs-0.7.2-6.el7_8.x86_64.rpm
-rw-r--r-- 1 root root 83764 Apr 28 2020 fuse3-libs-3.6.1-4.el7.x86_64.rpm
-rw-r--r-- 1 root root 83452 Apr 28 2020 slirp4netns-0.4.3-4.el7_8.x86_64.rpm
-rw-r--r-- 1 root root 40816 Jul 6 2020 container-selinux-2.119.2-1.911c772.el7_8.noarch.rpm
-rw-r--r-- 1 root root 30801216 Oct 11 21:15 docker-ce-cli-20.10.9-3.el7.x86_64.rpm
-rw-r--r-- 1 root root 23785744 Oct 11 21:15 docker-ce-20.10.9-3.el7.x86_64.rpm
-rw-r--r-- 1 root root 31304280 Oct 11 21:15 containerd.io-1.4.9-3.1.el7.x86_64.rpm
-rw-r--r-- 1 root root 8427040 Oct 11 21:15 docker-ce-rootless-extras-20.10.9-3.el7.x86_64.rpm
-rw-r--r-- 1 root root 4373740 Oct 11 21:15 docker-scan-plugin-0.8.0-3.el7.x86_64.rpm
下载完成后，即可使用下面的命令执行安装
$ rpm -ivh *.rpm
下载离线包的原因是因为我们在生产环境安装的时候，绝大多数的生产环境都是与外网隔离的，所以就需要提前下载好安装所需的离线rpm包。
