ubuntu18升级到20

替换版本号

sudo sed -i 's/bionic/focal/g' /etc/apt/sources.list

替换国内源

sudo sed -i "s@http://.*archive.ubuntu.com@http://repo.huaweicloud.com@g" /etc/apt/sources.list
sudo sed -i "s@http://.*security.ubuntu.com@http://repo.huaweicloud.com@g" /etc/apt/sources.list

更新升级

sudo apt update && sudo apt -y dist-upgrade