How to configure apt remote source in Ubuntu system

• Check the Unbuntu version and Codename:

  qv123@localhost:~$ lsb_release -a
  No LSB modules are available.
  Distributor ID: Ubuntu
  Description:    Ubuntu 22.04.3 LTS
  Release:    22.04
  Codename:   jammy              # 不同的版本apt源语句中就换不同的关键字

• backup file:

  cp /etc/apt/sources.list /opt/sources.list.bak

• Edit /etc/apt/sources.list File: (only root users can use eof)

  # Unbuntu20.4版本，20.4版本在安装的时候指定好Mirrors addresses再重启网络并且执行sudo apt-get clean && sudo apt-get upgrade && sudo apt-get update命令就可以正常使用apt命令，不必再配置yum源
  #添加阿里源
  cat << eof > /etc/apt/sources.list
  deb http://mirrors.aliyun.com/ubuntu focal main restricted
  deb http://mirrors.aliyun.com/ubuntu focal-updates main restricted
  deb http://mirrors.aliyun.com/ubuntu focal universe
  deb http://mirrors.aliyun.com/ubuntu focal-updates universe
  deb http://mirrors.aliyun.com/ubuntu focal multiverse
  deb http://mirrors.aliyun.com/ubuntu focal-updates multiverse
  deb http://mirrors.aliyun.com/ubuntu focal-backports main restricted universe multiverse
  deb http://mirrors.aliyun.com/ubuntu focal-security main restricted
  deb http://mirrors.aliyun.com/ubuntu focal-security universe
  deb http://mirrors.aliyun.com/ubuntu focal-security multiverse
  eof

  # Unbuntu22.4版，22.4版本在安装的时候指定好Mirrors addresses再重启网络并且执行sudo apt-get clean && sudo apt-get upgrade && sudo apt-get update命令就可以正常使用apt命令，不必再配置yum源
  #添加阿里源
  cat << eof > /etc/apt/sources.list
  deb http://mirrors.aliyun.com/ubuntu jammy main restricted
  deb http://mirrors.aliyun.com/ubuntu jammy-updates main restricted
  deb http://mirrors.aliyun.com/ubuntu jammy universe
  deb http://mirrors.aliyun.com/ubuntu jammy-updates universe
  deb http://mirrors.aliyun.com/ubuntu jammy multiverse
  deb http://mirrors.aliyun.com/ubuntu jammy-updates multiverse
  deb http://mirrors.aliyun.com/ubuntu jammy-backports main restricted universe multiverse
  deb http://mirrors.aliyun.com/ubuntu jammy-security main restricted
  deb http://mirrors.aliyun.com/ubuntu jammy-security universe
  deb http://mirrors.aliyun.com/ubuntu jammy-security multiverse
  eof

• Restart the network:

  sudo systemctl restart systemd-networkd

• Update the package list: Run the following command in the terminal for the changes to take effect:

  sudo apt-get clean && sudo apt-get upgrade && sudo apt-get update

• test:

  sudo apt install -y nginx