常见的Linux发行版本官方都提供了用于云环境（如OpenStack）的Image的下载.
| 发行版 | 下载地址 |
|---|---|
| fedora 30 | http://mirrors.ustc.edu.cn/fedora/releases/30/Cloud/x86_64/images/ |
| ubuntu 18.04 | http://cloud-images.ubuntu.com/bionic/current/ |
| centos-7.0-x86_64 | http://cloud.centos.org/centos/7/images/ |
| rhel-7.0-x86_64 | https://access.redhat.com/downloads/content/69/ver=/rhel---7/7.0/x86_64/product-downloads |