更新Debian 9

cp     /etc/apt/sources.list /etc/apt/sources.list.conf


cat > /etc/apt/sources.list <<EOF 
deb http://mirrors.aliyun.com/debian/ stretch main non-free contrib
deb-src http://mirrors.aliyun.com/debian/ stretch main non-free contrib
deb http://mirrors.aliyun.com/debian-security stretch/updates main
deb-src http://mirrors.aliyun.com/debian-security stretch/updates main
deb http://mirrors.aliyun.com/debian/ stretch-updates main non-free contrib
deb-src http://mirrors.aliyun.com/debian/ stretch-updates main non-free contrib
deb http://mirrors.aliyun.com/debian/ stretch-backports main non-free contrib
deb-src http://mirrors.aliyun.com/debian/ stretch-backports main non-free contrib
EOF



apt-get update