Ubuntu16.04升级到18.04的步骤

更新系统

sudo apt update

sudo apt upgrade -y

sudo apt dist-upgrade -y

删除无用的依赖
```
sudo apt-get autoremove -y
    
```

安装update-manager-core

sudo apt install update-manager-core -y

升级到18.04
```
sudo do-release-upgrade
    
```