Just try
sudo do-release-upgrade
if you get this
An upgrade from 'zesty' to 'bionic' is not supported with this tool.
you have to upgrade manually. Because 17.10 is end of life.
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Install
aptitude on 17.04 system with:
sudo apt-get install aptitude
If nothing else helps you can change old-releases.ubuntu.com back to archive.ubuntu.com and then zesty to arftul:
sudo sed -i -re 's/old-releases.ubuntu.com/archive.ubuntu.com/g' /etc/apt/sources.list sudo sed -i -re 's/zesty/artful/g' /etc/apt/sources.list
Or just change /etc/apt/sources.list to
deb https://mirrors.ustc.edu.cn/ubuntu-old-releases/ubuntu/ artful main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu-old-releases/ubuntu/ artful main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu-old-releases/ubuntu/ artful-security main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu-old-releases/ubuntu/ artful-security main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu-old-releases/ubuntu/ artful-updates main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu-old-releases/ubuntu/ artful-updates main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu-old-releases/ubuntu/ artful-backports main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu-old-releases/ubuntu/ artful-backports main restricted universe multiverse
And then upgrade system with
sudo aptitude update sudo aptitude dist-upgrade