ubuntu18.04 Update Source

There are many images of Ubuntu in China, including Ali, NetEase, and a lot of educational network sources, such as: Tsinghua source, Zhong Ke source.
Here we take the source of Zhong Ke as an example to explain how to modify Ubuntu 18.04 the default source.
To edit the /etc/apt/sources.list file, add the following entry at the top of the file (make the appropriate backup before doing the operation):

# #中科大源deb https://mirrors.ustc.edu.cn/ubuntu/bionic main restricted universe multiverseDEB-SRC https://mirrors.ustc.edu.cn/ubuntu/bionic main restricted universe multiverseDeb https://mirrors.ustc.edu.cn/ubuntu/bionic-updates main restricted universe multiverseDEB-SRC https://mirrors.ustc.edu.cn/ubuntu/bionic-updates main restricted universe multiverseDeb https://mirrors.ustc.edu.cn/ubuntu/bionic-backports main restricted universe multiverseDEB-SRC https://mirrors.ustc.edu.cn/ubuntu/bionic-backports main restricted universe multiverseDeb https://mirrors.ustc.edu.cn/ubuntu/bionic-security main restricted universe multiverseDEB-SRC https://mirrors.ustc.edu.cn/ubuntu/bionic-security main restricted universe multiverseDeb https://mirrors.ustc.edu.cn/ubuntu/bionic-proposed main restricted universe multiverseDEB-SRC https://mirrors.ustc.edu.cn/ubuntu/bionic-proposed main restricted universe multiverse

Then execute the command:

sudo apt-get  updatesudo apt-get Upgrade

Ali

Deb http://mirrors.aliyun.com/ubuntu/bionic main restricted universe multiverseDeb http://mirrors.aliyun.com/ubuntu/bionic-security main restricted universe multiverseDeb http://mirrors.aliyun.com/ubuntu/bionic-updates main restricted universe multiverseDeb http://mirrors.aliyun.com/ubuntu/bionic-proposed main restricted universe multiverseDeb http://mirrors.aliyun.com/ubuntu/bionic-backports main restricted universe multiverseDEB-SRC http://mirrors.aliyun.com/ubuntu/bionic main restricted universe multiverseDEB-SRC http://mirrors.aliyun.com/ubuntu/bionic-security main restricted universe multiverseDEB-SRC http://mirrors.aliyun.com/ubuntu/bionic-updates main restricted universe multiverseDEB-SRC http://mirrors.aliyun.com/ubuntu/bionic-proposed main restricted universe multiverseDEB-SRC http://mirrors.aliyun.com/ubuntu/bionic-backports main restricted universe multiverse

163 source

Deb http://mirrors.163.com/ubuntu/bionic main restricted universe multiverseDeb http://mirrors.163.com/ubuntu/bionic-security main restricted universe multiverseDeb http://mirrors.163.com/ubuntu/bionic-updates main restricted universe multiverseDeb http://mirrors.163.com/ubuntu/bionic-proposed main restricted universe multiverseDeb http://mirrors.163.com/ubuntu/bionic-backports main restricted universe multiverseDEB-SRC http://mirrors.163.com/ubuntu/bionic main restricted universe multiverseDEB-SRC http://mirrors.163.com/ubuntu/bionic-security main restricted universe multiverseDEB-SRC http://mirrors.163.com/ubuntu/bionic-updates main restricted universe multiverseDEB-SRC http://mirrors.163.com/ubuntu/bionic-proposed main restricted universe multiverseDEB-SRC http://mirrors.163.com/ubuntu/bionic-backports main restricted universe multiverse

Tsinghua Source

Deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic main restricted universe multiverseDEB-SRC https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic main restricted universe multiverseDeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic-updates main restricted universe multiverseDEB-SRC https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic-updates main restricted universe multiverseDeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic-backports main restricted universe multiverseDEB-SRC https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic-backports main restricted universe multiverseDeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic-security main restricted universe multiverseDEB-SRC https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic-security main restricted universe multiverseDeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic-proposed main restricted universe multiverseDEB-SRC https://mirrors.tuna.tsinghua.edu.cn/ubuntu/bionic-proposed main restricted universe multiverse

ubuntu18.04 Update Source