lsb_release 查看 Ubuntu 版本

在 VMware 上安装了一个 Ubuntu20.04 的虚拟机， lsb_release -a 显示如下信息：

  1. $ lsb_release -a
  2. No LSB modules are available.
  3. Distributor ID: Ubuntu
  4. Description:    Ubuntu 20.04 LTS
  5. Release:        20.04
  6. Codename:       focal

sources.list

  1. $ cat /etc/apt/sources.list
  2. deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
  4. deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
  8. deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
  10. deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
  14. deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
  16. deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
  18. deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
  20. deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
  22. deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
  24. deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse

虽然上面的地址对应的是 Codename 为 bionic（18.04.5 LTS）的 Ubuntu 版本，而 Ubuntu 20.04 LTS 的 Codename 为 focal，然而能正常工作。
反而网上 focal 版本的阿里镜像源不能工作~~