cp /etc/apt/sources.list /etc/apt/sources.list.bak

腾讯云源

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

deb-src http://mirrors.cloud.tencent.com/debian-security buster/updates main
deb-src http://mirrors.cloud.tencent.com/debian/ buster main non-free contrib
deb-src http://mirrors.cloud.tencent.com/debian/ buster-updates main non-free contrib
deb-src http://mirrors.cloud.tencent.com/debian/ buster-backports main non-free contrib
EOF

华为源

cat <<EOF > /etc/apt/sources.list 
deb https://mirrors.huaweicloud.com/debian/ buster main contrib non-free
deb https://mirrors.huaweicloud.com/debian/ buster-updates main contrib non-free
deb https://mirrors.huaweicloud.com/debian/ buster-backports main contrib non-free
deb https://mirrors.huaweicloud.com/debian-security/ buster/updates main contrib non-free

deb-src https://mirrors.huaweicloud.com/debian/ buster main contrib non-free
deb-src https://mirrors.huaweicloud.com/debian/ buster-updates main contrib non-free
deb-src https://mirrors.huaweicloud.com/debian/ buster-backports main contrib non-free 

阿里云源

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

deb-src http://mirrors.aliyun.com/debian-security buster/updates main
deb-src http://mirrors.aliyun.com/debian/ buster main non-free contrib
deb-src http://mirrors.aliyun.com/debian/ buster-updates main non-free contrib
deb-src http://mirrors.aliyun.com/debian/ buster-backports main non-free contrib
EOF

apt update