一、更换国内源
1、修改 /etc/apt/sources.list
sudo nano /etc/apt/sources.list
将http://mirrordirector.raspbian.org/raspbian/替换为http://mirrors.aliyun.com/raspbian/raspbian/
2、修改/etc/apt/sources.list.d/raspi.list
sudo nano /etc/apt/sources.list.d/raspi.list
将http://archive.raspberrypi.org/debian/替换为http://mirrors.ustc.edu.cn/archive.raspberrypi.org/debian/
3、更新软件源
sudo apt-get update