1.编辑 /etc/apt/sources.list

deb http://mirrors.tencentyun.com/ubuntu/ bionic main restricted universe multiverse

deb http://mirrors.tencentyun.com/ubuntu/ bionic-security main restricted universe multiverse

deb http://mirrors.tencentyun.com/ubuntu/ bionic-updates main restricted universe multiverse

#deb http://mirrors.tencentyun.com/ubuntu/ bionic-proposed main restricted universe multiverse

#deb http://mirrors.tencentyun.com/ubuntu/ bionic-backports main restricted universe multiverse

deb-src http://mirrors.tencentyun.com/ubuntu/ bionic main restricted universe multiverse

deb-src http://mirrors.tencentyun.com/ubuntu/ bionic-security main restricted universe multiverse

deb-src http://mirrors.tencentyun.com/ubuntu/ bionic-updates main restricted universe multiverse

#deb-src http://mirrors.tencentyun.com/ubuntu/ bionic-proposed main restricted universe multiverse

#deb-src http://mirrors.tencentyun.com/ubuntu/ bionic-backports main restricted universe multiverse

2.把上方腾讯云的apt源替换至sources.list文件中

3.刷新软件源信息：

sudo apt update

4.更新软件

sudo apt upgrade