亲测 kali的官方源也很快 所以可换可不换
由于更新安装在sources.list中还加入了debain的网易（163）源
vim /etc/apt/sources.list
#kali 官方源 deb http://http.kali.org/kali kali-rolling main non-free contrib deb-src http://http.kali.org/kali kali-rolling main non-free contrib # 网易源 deb http://mirrors.163.com/debian/ stretch main non-free contrib deb http://mirrors.163.com/debian/ stretch-updates main non-free contrib deb http://mirrors.163.com/debian/ stretch-backports main non-free contrib deb-src http://mirrors.163.com/debian/ stretch main non-free contrib deb-src http://mirrors.163.com/debian/ stretch-updates main non-free contrib deb-src http://mirrors.163.com/debian/ stretch-backports main non-free contrib deb http://mirrors.163.com/debian-security/ stretch/updates main non-free contrib deb-src http://mirrors.163.com/debian-security/ stretch/updates main non-free contrib