Ubuntu16.04换成清华大学源

第一：备份源文件
cd /etc/apt/
然后会显示下面的源文件sources.list
输入命令
sudo cp sources.list sources.list.bak
就是将sources.list备份到sources.list.bak

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第二步：替换源文件
清华大学源

默认注释了源码镜像以提高 apt update 速度，如有需要可自行取消注释

deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial main restricted universe multiverse

deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial main restricted universe multiversedeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates main restricted universe multiverse

deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates main restricted universe multiversedeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse

deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-backports main restricted universe multiversedeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security main restricted universe multiverse

deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-security main restricted universe multiverse

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预发布软件源，不建议启用

deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-proposed main restricted universe multiverse

deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-proposed main restricted universe multiversesudo gedit sources.list

打开文件，将里面的代码替换成上面的代码即可

第三步：更新源

sudo apt-get update 更新源
sudo apt-get upgrade 更新软件
参考网站：https://blog.csdn.net/dty306034831/article/details/79188808