because the default source of Ubuntu is foreign, download software is very slow, and often download failure, the following is mainly a way to add a domestic source as a software download source of the simple method.
1. Path to the configuration file for the software download Source:/etc/apt/sources.list
2. Add the download source address
(1) Open "Software&updates". Double-clicking the "sources.list" file directly also opens "Software&updates". The Display dialog box looks like this.
(2) Click "Other Software" and "Add ..." To open the dialog box below.
(3) Add the download source address you want to add to "APT line" and click "Add Source".
3. Update the source list
sudo apt-get update
sudo apt-get upgrade
Attachments: Download source addresses collected from the network:
#tsing Hua Mirror site
Deb Http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial main Multiverse restricted universe
Deb Http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial-backports main Multiverse restricted universe
Deb http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial-proposed main Multiverse restricted universe
Deb Http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial-security main Multiverse restricted universe
Deb Http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial-updates main Multiverse restricted universe
DEB-SRC http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial main Multiverse restricted universe
DEB-SRC http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial-backports main Multiverse restricted universe
DEB-SRC http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial-proposed main Multiverse restricted universe
DEB-SRC http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial-security main Multiverse restricted universe
DEB-SRC http://mirrors.tuna.tsinghua.edu.cn/ubuntu/xenial-updates main Multiverse restricted universe
#163 Mirror Site
Deb Http://mirrors.163.com/debian/lenny main contrib Non-free
Deb-src Http://mirrors.163.com/debian Lenny Main contrib Non-free
Deb Http://mirrors.163.com/debian-security/stable/updates Main
DEB-SRC Http://mirrors.163.com/debian-security/stable/updates Main
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
#official Mirror Site
Deb Http://ftp.debian.org/debian/lenny main contrib Non-free
DEB-SRC Http://ftp.debian.org/debian/lenny Main contrib Non-free
Deb Http://ftp.us.debian.org/debian/lenny main contrib Non-free
DEB-SRC Http://ftp.us.debian.org/debian/lenny Main contrib Non-free
Deb Http://security.debian.org/stable/updates Main
DEB-SRC Http://security.debian.org/stable/updates Main
Deb Http://volatile.debian.org/debian-volatile stable/volatile Main
DEB-SRC Http://volatile.debian.org/debian-volatile Stable/volatile Main
# USTC Debian-multimedia
Deb Http://debian.ustc.edu.cn/debian-multimedia/stable Main
DEB-SRC http://debian.ustc.edu.cn/debian-multimedia/stable Main
# USTC Debian-security
Deb Http://debian.ustc.edu.cn/debian-security/stable/updates main Non-free contrib
DEB-SRC http://debian.ustc.edu.cn/debian-security/stable/updates main Non-free contrib
Configuring the Linux software download source (Ubuntu)