1、備份源
# sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
2、編輯源文件/etc/apt/sources.list，並添加以下地址
# sudo gedit /etc/apt/sources.list
網易163源：
deb http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse deb http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse deb-src http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse
搜狐源：
deb http://mirrors.sohu.com/ubuntu/ trusty main restricted universe multiverse deb http://mirrors.sohu.com/ubuntu/ trusty-security main restricted universe multiverse deb http://mirrors.sohu.com/ubuntu/ trusty-updates main restricted universe multiverse deb http://mirrors.sohu.com/ubuntu/ trusty-proposed main restricted universe multiverse deb http://mirrors.sohu.com/ubuntu/ trusty-backports main restricted universe multiverse deb-src http://mirrors.sohu.com/ubuntu/ trusty main restricted universe multiverse deb-src http://mirrors.sohu.com/ubuntu/ trusty-security main restricted universe multiverse deb-src http://mirrors.sohu.com/ubuntu/ trusty-updates main restricted universe multiverse deb-src http://mirrors.sohu.com/ubuntu/ trusty-proposed main restricted universe multiverse deb-src http://mirrors.sohu.com/ubuntu/ trusty-backports main restricted universe multiverse
OSChina源：
deb http://mirrors.oschina.net/ubuntu/ trusty main restricted universe multiverse deb http://mirrors.oschina.net/ubuntu/ trusty-backports main restricted universe multiverse deb http://mirrors.oschina.net/ubuntu/ trusty-proposed main restricted universe multiverse deb http://mirrors.oschina.net/ubuntu/ trusty-security main restricted universe multiverse deb http://mirrors.oschina.net/ubuntu/ trusty-updates main restricted universe multiverse deb-src http://mirrors.oschina.net/ubuntu/ trusty main restricted universe multiverse deb-src http://mirrors.oschina.net/ubuntu/ trusty-backports main restricted universe multiverse deb-src http://mirrors.oschina.net/ubuntu/ trusty-proposed main restricted universe multiverse deb-src http://mirrors.oschina.net/ubuntu/ trusty-security main restricted universe multiverse deb-src http://mirrors.oschina.net/ubuntu/ trusty-updates main restricted universe multiverse
3、 更新源索引，使新源生效
# sudo apt-get update
Ubuntu armhf版本的源網址不同於普通Ubuntu系統，如果採用如下網址會出現問題，導致sudo apt-get update出現Error。
deb http://archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ trusty-proposed main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
應該要採用如下網址：
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty main multiverse restricted universe
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty-backports main multiverse restricted universe
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty-proposed main multiverse restricted universe
deb http://mirrors.ustc.edu.cn/ubuntu-ports trusty-security main multiverse restricted universe
deb http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty-updates main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty-backports main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty-proposed main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty-security main multiverse restricted universe
deb-src http://mirrors.ustc.edu.cn/ubuntu-ports/ trusty-updates main multiverse restricted universe