目录
配置文件更新:
1.打开终端
【ctrl+alt+t】
2.备份原有的配置文件
【cp /etc/apt/sources.list /etc/apt/sources.list.bak_yyyymmdd】
3.打开配置文件
【vim /etc/apt/sources.list】
没有vim 可以安装 sudo apt-get install vim
4.配置文件末尾添加国内源：
国内源速度快，没有限制【下边任选一个 添加】
5.文件生效：
【source /etc/profile】
6.更新源和系统：
【sudo apt-get upgrade】
【sudo apt-get update】
7.重启系统：
【reboot】
#阿里源地址
deb ubuntu安装包下载_开源镜像站-阿里云 bionic main restricted universe multiverse
deb ubuntu安装包下载_开源镜像站-阿里云 bionic-security main restricted universe multiverse
deb ubuntu安装包下载_开源镜像站-阿里云 bionic-updates main restricted universe multiverse
deb ubuntu安装包下载_开源镜像站-阿里云 bionic-proposed main restricted universe multiverse
deb ubuntu安装包下载_开源镜像站-阿里云 bionic-backports main restricted universe multiverse
deb-src ubuntu安装包下载_开源镜像站-阿里云 bionic main restricted universe multiverse
deb-src ubuntu安装包下载_开源镜像站-阿里云 bionic-security main restricted universe multiverse
deb-src ubuntu安装包下载_开源镜像站-阿里云 bionic-updates main restricted universe multiverse
deb-src ubuntu安装包下载_开源镜像站-阿里云 bionic-proposed main restricted universe multiverse
deb-src ubuntu安装包下载_开源镜像站-阿里云 bionic-backports main restricted universe multiverse
#华为源地址
deb https://repo.huaweicloud.com/ubuntu/ focal main restricted
deb https://repo.huaweicloud.com/ubuntu/ focal-updates main restricted
deb https://repo.huaweicloud.com/ubuntu/ focal universe
deb https://repo.huaweicloud.com/ubuntu/ focal-updates universe
deb https://repo.huaweicloud.com/ubuntu/ focal-backports main restricted universe
deb https://repo.huaweicloud.com/ubuntu/ focal-security main restricted
deb https://repo.huaweicloud.com/ubuntu/ focal-security universe
#中科大源地址
deb Index of /ubuntu/ bionic main restricted universe multiverse
deb-src Index of /ubuntu/ bionic main restricted universe multiverse
deb Index of /ubuntu/ bionic-updates main restricted universe multiverse
deb-src Index of /ubuntu/ bionic-updates main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb-src Index of /ubuntu/ bionic-backports main restricted universe multiverse
deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
deb Index of /ubuntu/ bionic-proposed main restricted universe multiverse
deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
#163源地址
deb Index of /ubuntu/ bionic main restricted universe multiverse
deb Index of /ubuntu/ bionic-security main restricted universe multiverse
deb Index of /ubuntu/ bionic-updates main restricted universe multiverse
deb Index of /ubuntu/ bionic-proposed main restricted universe multiverse
deb Index of /ubuntu/ bionic-backports main restricted universe multiverse
deb-src Index of /ubuntu/ bionic main restricted universe multiverse
deb-src Index of /ubuntu/ bionic-security main restricted universe multiverse
deb-src Index of /ubuntu/ bionic-updates main restricted universe multiverse
deb-src Index of /ubuntu/ bionic-proposed main restricted universe multiverse
deb-src Index of /ubuntu/ bionic-backports main restricted universe multiverse
#清华源地址
deb Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic main restricted universe multiverse
deb-src Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic main restricted universe multiverse
deb Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic-updates main restricted universe multiverse
deb-src Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic-updates main restricted universe multiverse
deb Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic-backports main restricted universe multiverse
deb-src Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic-backports main restricted universe ultiverse
deb Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic-security main restricted universe multiverse
deb-src Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic-security main restricted universe multiverse
deb Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic-proposed main restricted universe multiverse
deb-src Index of /ubuntu/ | 清华大学开源软件镜像站 | Tsinghua Open Source Mirror bionic-proposed main restricted universe ultiverse
图形设置：
选中中国源的一个，这里暂时选择阿里云
安装完成