luozw@luozw-vpc:/etc/apt/apt.conf.d$ sudo apt-get update
Failed to start apt-news.service: Unit apt-news.service not found.
Failed to start esm-cache.service: Unit esm-cache.service not found.
命中:1 http://mirrors.tuna.tsinghua.edu.cn/ubuntu bionic InRelease
命中:2 http://mirrors.tuna.tsinghua.edu.cn/ubuntu bionic-updates InRelease
命中:3 http://mirrors.tuna.tsinghua.edu.cn/ubuntu bionic-backports InRelease
命中:4 http://mirrors.tuna.tsinghua.edu.cn/ubuntu bionic-security InRelease
正在读取软件包列表... 完成

cd /etc/apt/apt.conf.d
sudo mkdir off
sudo mv 20apt-esm-hook.conf off