添加sudo:
su
apt-get install sudo
修改sudoers:
vi /etc/sudoers
在%sudo ALL=(ALL:ALL) ALL 下添加
yourusername ALL=(ALL:ALL) ALL
修改源:
vi /etc/apt/sources.list
# deb cdrom:[Debian GNU/Linux 9.8.0 _Stretch_ - Official amd64 DVD Binary-1 20190415-12:12]/ stretch contrib main
deb http://mirrors.ustc.edu.cn/debian/ stretch main non-free contrib
deb http://mirrors.ustc.edu.cn/debian/ stretch-updates main non-free contrib
deb http://mirrors.ustc.edu.cn/debian/ stretch-backports main non-free contrib
deb-src http://mirrors.ustc.edu.cn/debian/ stretch main non-free contrib
deb-src http://mirrors.ustc.edu.cn/debian/ stretch-updates main non-free contrib
deb-src http://mirrors.ustc.edu.cn/debian/ stretch-backports main non-free contrib
apt-get update