最近装了ubuntu18.04 LTS，下载软件有点慢，网上搜了下解决方案，大致是两种：一、把/etc/apt/sources.list文件里的源更换一下，改成阿里云或者其它的镜像的文件；二、更换software&updates里的select best server。

一、更换/etc/apt/sources.list文件里的源

1. 备份源列表

Ubuntu配置的默认源并不是国内的服务器，下载更新软件都比较慢。首先备份源列表文件sources.list：

1.   # 首先备份源列表
2.   sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup

2. 打开sources.list文件修改

选择合适的源，替换原文件的内容，保存编辑好的文件, 以阿里云更新服务器为例（可以分别测试阿里云、清华、中科大、163源的速度，选择最快的）：

1.   # 打开sources.list文件
2.   sudo gedit /etc/apt/sources.list

编辑/etc/apt/sources.list文件, 在文件最前面添加阿里云镜像源：

1.   # 阿里源
2.   deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
3.   deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
4.   deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
5.   deb http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
6.   deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
7.   deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted universe multiverse
8.   deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted universe multiverse
9.   deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted universe multiverse
10.   deb-src http://mirrors.aliyun.com/ubuntu/ bionic-proposed main restricted universe multiverse
11.   deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse

3. 刷新列表

1.   sudo apt-get update
2.   sudo apt-get install build-essential

此时下载速度就明显加快了

4. 其他源

中科大源：

1.   # 中科大源
2.   deb https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse
3.   deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse
4.   deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
5.   deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
6.   deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
7.   deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
8.   deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
9.   deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
10.   deb https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
11.   deb-src https://mirrors.ustc.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse

163源：

1.   # 163源
2.   deb http://mirrors.163.com/ubuntu/ bionic main restricted universe multiverse
3.   deb http://mirrors.163.com/ubuntu/ bionic-security main restricted universe multiverse
4.   deb http://mirrors.163.com/ubuntu/ bionic-updates main restricted universe multiverse
5.   deb http://mirrors.163.com/ubuntu/ bionic-proposed main restricted universe multiverse
6.   deb http://mirrors.163.com/ubuntu/ bionic-backports main restricted universe multiverse
7.   deb-src http://mirrors.163.com/ubuntu/ bionic main restricted universe multiverse
8.   deb-src http://mirrors.163.com/ubuntu/ bionic-security main restricted universe multiverse
9.   deb-src http://mirrors.163.com/ubuntu/ bionic-updates main restricted universe multiverse
10.   deb-src http://mirrors.163.com/ubuntu/ bionic-proposed main restricted universe multiverse
11.   deb-src http://mirrors.163.com/ubuntu/ bionic-backports main restricted universe multiverse

清华源：

1.   # 清华源
2.   deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse
3.   deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse
4.   deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
5.   deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
6.   deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
7.   deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
8.   deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
9.   deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
10.   deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
11.   deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse

更换sources.list速度依然还是很慢就请继续往下看第二种方法。

二、更换software&updates里的select best server

这种方法不需要改什么文件，直接在select best server里自动选择。
1. 首先按 WIN键,搜索 software,找到 software&updates.

2. 然后点进去,在 Download from里面选择 other

3. 然后点击 select best server按钮,它会找到最快的那个（最好选比较常用的源，如：清华源，阿里源或者163源之类的这样会比较稳定）,然后点击 choose server,就选好镜像啦.

5. 然后在terminal里面输入

sudo apt-get update

看看是不是已经加速了呀！