问题描述：
多次在apt install时候遇到E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing? 的error。
Error报的信息显示是这个包向source里的资源下载失败了，但是原因是多种多样的，这里做了个总结，以防下次踩坑：
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问题解决：
1- source本身的问题
根据提示，我们首先应当 apt-get update 一下source,如果在apt-get update后依然报这个error，那就说明这个source本省就有错误，尝试apt-get update --fix-missing后依旧报这个error，果断换source。
输入命令：
sudo cp sources.list sources.list.bak
就是先将sources.list备份到sources.list.bak
**将 /etc/apt/sources.list 的内容换成：
**
# deb cdrom:[Ubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1)]/ xenial main restricted
deb-src http://archive.ubuntu.com/ubuntu xenial main restricted #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb http://mirrors.aliyun.com/ubuntu/ xenial multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse #Added by software-properties
deb http://archive.canonical.com/ubuntu xenial partner
deb-src http://archive.canonical.com/ubuntu xenial partner
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security multiverse
更多源请参考：https://www.cnblogs.com/X-knight/p/10598498.html
最后sudo apt-get update一下就OK了。
2- 网络的问题
网关错误拦截了数据包或者防火墙故意将其屏蔽在外（比方update 包含有google-chrome浏览器的source时候，ip 会自动重定向至6.6.6.6）
sudo vim /etc/resolv.conf
添加：
nameserver 8.8.8.8
nameserver 223.5.5.5
nameserver 223.6.6.6
或是换网络试一下或者参见该配置代理即可。
最后sudo apt-get update一下就OK了。