为了提高软件安装，升级速度，需要我们将树莓派或其他linux系统软件园，改为国内镜像地址（本例使用中科大镜像源）。
1 lsb_release -c
注：版本有:/ jessie / wheezy / squeeze / stretch / buster
1 stretch
1 deb http://mirrors.ustc.edu.cn/raspbian/raspbian/ stretch main contrib non-free rpi 2 deb-src http://mirrors.ustc.edu.cn/raspbian/raspbian/ stretch main contrib non-free rpi
或者在命令行执行：
1 sudo sed -i ‘s#://mirrordirector.raspbian.org#s://mirrors.ustc.edu.cn/raspbian#g‘ /etc/apt/sources.list 2 sudo sed -i ‘s#://archive.raspberrypi.org/debian#s://mirrors.ustc.edu.cn/archive.raspberrypi.org#g‘ /etc/apt/sources.list.d/raspi.lis
1 deb http://mirrors.ustc.edu.cn/archive.raspberrypi.org/ stretch main ui 2 deb-src http://mirrors.ustc.edu.cn/archive.raspberrypi.org/ stretch main ui
1 sudo apt-get update
1 sudo apt-get -y upgrade
原文：https://www.cnblogs.com/everythingisfile/p/12071515.html