安装IOM时docker无法安装

正在处理依赖关系systemd=219-78.el7,它被软件包systemd-python-219-78.el7.x86_64需要
Loading mirror speeds from cached hostfile
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=76arch=x86 646repo=os&infra=stock
error was

14:curl#6·"Could not resolve host:mirrorlist.centos.0rgi未知的错误”

One of the configured repositories failed(未知)，

Cannot find a valid baseurl for repo:base/7/x86 64
Failed to install Docker.Please check the cause and try again...

手动安装docker即可

手动安装docker步骤：https://support.sangfor.com.cn/cases/list?product_id=26&type=1&category_id=28148&isOpen=true