修改源
1 deb http://mirrors.yun-idc.com/ubuntu/ bionic main restricted universe multiverse 2 deb http://mirrors.yun-idc.com/ubuntu/ bionic-security main restricted universe multiverse 3 deb http://mirrors.yun-idc.com/ubuntu/ bionic-updates main restricted universe multiverse
原文：https://www.cnblogs.com/iblackly/p/11745769.html