Debian From Scratch方法

Debian From Scratch (DFS): A Step-by-Step Guide to Building a Custom Debian System
Debian From Scratch is a project that empowers users to create a fully customized Debian system from the ground up by compiling and configuring all core components (kernel, libraries, tools). This process is ideal for advanced users who want deep control over system behavior, optimization for specific hardware, or a minimal runtime environment. Below is a structured guide to the DFS workflow:

1. Preparation Phase

Before starting, ensure your environment meets the following requirements:

• Hardware: A Linux-based build machine with at least 10GB of disk space (for temporary compilation files) and sufficient RAM (2GB+ recommended).
• Dependencies: Install essential build tools via apt-get (Debian/Ubuntu) or your distribution’s package manager:

  sudo apt-get install build-essential gcc make debhelper fakeroot bc bison flex libncurses-dev
  

• Source Code: Download the latest Debian stable source packages (e.g., debian-archive-keyring, linux-source, glibc-source) from the official Debian website or mirrors. Store them in a dedicated directory (e.g., ~/dfs_sources).

2. Kernel Compilation

The kernel is the heart of your custom system. Follow these steps to build it:

• Extract the kernel source:

  tar -xvf linux-source-*.tar.xz -C ~/dfs_build/
  cd ~/dfs_build/linux-source-*
  

• Configure the kernel: Run make menuconfig (text-based GUI) to enable/disable drivers/features (e.g., CPU architecture, filesystem support). For most users, the default “General Setup” options work, but you may need to adjust network or storage drivers for your hardware.
• Compile and install:

  make -j$(nproc)          # Use all available CPU cores for faster compilation
  sudo make modules_install
  sudo make install        # Installs the kernel to /boot/
  

• Update the bootloader (GRUB): Run sudo update-grub to add the new kernel to the boot menu.

3. Base System Construction

Compile and install core system components to form a functional base:

• C Library (glibc): Extract the glibc source and compile with:

  tar -xvf glibc-source-*.tar.xz -C ~/dfs_build/
  cd ~/dfs_build/glibc-*
  mkdir build && cd build
  ../configure --prefix=/usr --disable-werror
  make -j$(nproc)
  sudo make install
  

• Shell & Core Utilities: Install bash, coreutils, findutils, and grep from source or use debootstrap to fetch pre-built binaries (faster for beginners). For example, with debootstrap:

  sudo debootstrap stable /mnt/debian http://deb.debian.org/debian
  

  This creates a minimal Debian root filesystem in /mnt/debian.
• Package Management: Install apt and dpkg to handle future software installations. These tools simplify dependency resolution and package installation.

4. Root Filesystem Setup

Populate the root filesystem (/) with essential directories and files:

• Mount the target filesystem (e.g., a new partition or loopback device) to /mnt/debian:

  sudo mount /dev/sdXn /mnt/debian  # Replace sdXn with your target partition
  sudo mkdir -p /mnt/debian/{dev,proc,sys}
  sudo mount --bind /dev /mnt/debian/dev
  sudo mount --bind /proc /mnt/debian/proc
  sudo mount --bind /sys /mnt/debian/sys
  

• Copy compiled components: Use rsync or cp to transfer files from the build directory to /mnt/debian. For example:

  rsync -a ~/dfs_build/linux-source-*/arch/x86/boot/bzImage /mnt/debian/boot/vmlinuz-$(uname -r)
  

• Create critical device files: Run sudo mknod /mnt/debian/dev/console c 5 1 and other necessary device nodes (refer to linux-source/Documentation/devices.txt for details).

5. System Configuration

Customize the system to meet your needs:

• Hostname: Set the hostname by editing /mnt/debian/etc/hostname:

  echo "my-custom-system" | sudo tee /mnt/debian/etc/hostname
  

• Timezone: Configure the timezone using timedatectl (if installed) or by symlinking the appropriate zoneinfo file:

  sudo ln -sf /usr/share/zoneinfo/America/New_York /mnt/debian/etc/localtime
  

• Network: Edit /mnt/debian/etc/network/interfaces for static/DHCP configuration (see Network Setup section below).
• Users: Create a root password and a regular user with adduser:

  chroot /mnt/debian adduser myuser
  chroot /mnt/debian usermod -aG sudo myuser  # Add user to sudo group
  

6. Bootstrapping with debootstrap (Alternative Method)

For a quicker DFS setup, use debootstrap to create a minimal Debian system without full compilation:

• Install debootstrap:

  sudo apt-get install debootstrap
  

• Create a minimal system:

  sudo debootstrap stable /mnt/debian http://deb.debian.org/debian
  

• Chroot into the new system to configure it:

  sudo chroot /mnt/debian /bin/bash
  

• Proceed with hostname, timezone, and user setup as described above.

7. Testing & Deployment

• Test the System: Boot from the target partition (or a live USB) to verify the system starts correctly. Check logs (dmesg, /var/log/syslog) for errors.
• Package Installation: Use apt to install additional software (e.g., sudo apt install vim git).
• Deployment: Once tested, duplicate the root filesystem to other machines (using dd or imaging tools) or create a custom Debian ISO for easy distribution.

Key Notes for Success

• Backup Regularly: Compilation and installation can overwrite critical files. Always back up your data before starting.
• Consult Documentation: Refer to the official Debian From Scratch wiki and man pages (e.g., man make, man debootstrap) for detailed guidance.
• Start Small: If you’re new to system building, begin with a minimal configuration (e.g., no GUI) and gradually add components.

By following these steps, you can create a tailored Debian system optimized for your hardware and use case.