连接失败 [IP: 91.189.91.39 80]
错误:729 http://cn.archive.ubuntu.com/ubuntu focal/universe amd64 libgeos-3.8.0 amd64 3.8.0-1build1
  连接失败 [IP: 91.189.91.39 80]
错误:730 http://cn.archive.ubuntu.com/ubuntu focal/universe amd64 libgeos-c1v5 amd64 3.8.0-1build1
  连接失败 [IP: 91.189.91.39 80]
忽略:731 http://cn.archive.ubuntu.com/ubuntu focal/universe amd64 proj-data all 6.3.1-1
错误:732 http://cn.archive.ubuntu.com/ubuntu focal/universe amd64 libproj15 amd64 6.3.1-1
  连接失败 [IP: 91.189.91.39 80]
错误:733 http://cn.archive.ubuntu.com/ubuntu focal/universe amd64 libgeotiff5 amd64 1.5.1-2
  连接失败 [IP: 91.189.91.39 80]
错误:734 http://cn.archive.ubuntu.com/ubuntu focal/universe amd64 libhdf4-0-alt amd64 4.2.14-1ubuntu1
  连接失败 [IP: 91.189.91.39 80]

 https://icode9.com/content-3-1328417.html

步骤：

1、这里使用终端输入以下代码

sudo nautilus

 2、找到/etc/apt/sorces.list文件用文本编辑器打开后ctrl+A全选之后ctrl+V替换位如下代码

deb http://mirrors.163.com/ubuntu/ focal main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ focal-security main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ focal-updates main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ focal-proposed main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ focal-backports main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal-proposed main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal-backports main restricted universe multiverse

        注意：这里的“focal”是ubuntu20.04的版本代号，如果你不是ubuntu20.04需要查询你的版本代号，在终端通过如下命令查看：

lsb_release -a

之后的codename后便是你的版本代号，然后将你的版本代号代替所有focal就行。

操作完之后可以重新打开一个终端输入：

sudo apt-get update

就可以全部很快的下载完成了哦

原文地址：https://www.cnblogs.com/to-here/p/16108260.html