Create a small linux system named mylinux

Make a small linux system named mylinux-general Linux technology-Linux programming and kernel information. For more information, see the following. Use the grub boot program to guide the compiled Kernel File bzImage, convert the file system into a ramdisk image file, and load the image file in the memory to inject the file system; the command generates the bin and sbin files by compiling busybox. Note:

Kernel File + File System Image File + grub boot program <= 1440 K

Detailed steps:

1. Install grub on a floppy disk)

The procedure is as follows:

# Mke2fs/dev/fd0

An ext2 file is created.

# Mount/dev/fd0/mnt/floppy

Now, create some directories and copy some key files to the floppy disk:

# Mkdir/mnt/floppy/boot

# Mkdir/mnt/floppy/boot/grub

# Cp/boot/grub/stage1/mnt/floppy/boot/grub

# Cp/boot/grub/stage2/mnt/floppy/boot/grub


Run the grub command

At the grub> prompt, enter:

Grub> root (fd0)

Grub> setup (fd0)

Grub> quit

Boot Disk complete.


2. Configure busybox

Create a directory to store data:

# Mkdir/floppylinux

Use make menuconfig to configure busybox

# Cpbusybox-1.00.tar.gz/floppylinux

# Cd/floppylinux

# Tar xvfz busybox-1.00.tar.gz

# Cd busybox-1.00

# Make menuconfig

The following are functional options that need to be compiled into busybox,


General Configuration options

Show verbose applet usage messages

Runtime SUID/SGID configuration via/etc/busybox. conf

Build Options

Build BusyBox as a static binary (no shared libs)

Installation Options

Don't use/usr

Other options are some basic linux Command Options default

After configuration, exit and save.


Compile and install busybox


# Make

# Make install

After compilation, generate the subdirectory _ install in the busybox directory. The content is as follows:

Drwxr-xr-x 2 root 4096 November 24 15:28 bin

Lrwxrwxrwx 1 root 11 November 24 15:28 linuxrc-> bin/busybox

Drwxr-xr-x 2 root 4096 November 24 15:28 sbin

The executable file busybox is in the bin directory, and all others point to its symbolic link.


3. Create a root file system

Create a temporary directory, which is a floppy File System

# Mkdir/tmp/floppy-linux

Copy the files in the _ install directory in busybox:

# Cp./_ install/tmp/floppy-linux? R


# Cd/tmp/floppy-linux

# Mkdir dev etc/init. d proc mnt tmp var

# Chmod 755 dev etc/init. d bin mnt tmp var

# Chmod 555 proc

# Cd dev

# Mknod tty c 5 0

# Mknod console c 5 1

# Chmod 666 tty console

# Mknod tty0 c 4 0

# Chmod 666 tty0

# Mknod ram0 B 1 0

# Chmod 600 ram0

# Mknod fd0 B 2 0

# Chmod 600 fd0

# Mknod null c 1 3

# Chmod 666 null


Create the startup configuration file:

/Etc/inittab,

/Etc/init. d/rcS,

/Etc/fstab

/Boot/grub. conf

/Boot/menu. lst

Where

# Ln? S grub. conf menu. lst

Initab:

: Sysinit:/etc/init. d/rcS

: Askfirst:/bin/sh


RcS:

#! /Bin/sh

Mount? A

# Chmod 755 rc. sysinit


Fstab:

Proc/proc defaults 0 0


Grub. conf:

Timeout 10

Default 0

Title FloppyLinux root (fd0) kernel/boot/bzImage initrd/initrd.img.gz


4. Create an image file for Ramdisk:

# Dd if =/dev/zero of =/dev/ram1

Dd: Writing '/dev/ram1': the device has no space.

Read 8193 + 0 blocks

Output 8192 + 0 blocks

# Mke2fs-m0/dev/ram1

# Mkdir/mnt/ram

# Mount/dev/ram1/mnt/ram

Copy the previously prepared floppylinux root file system to ram1.

# Cp-R/tmp/floppy-linux/*/mnt/ram

# Umount/dev/ram1

# Dd if =/dev/ram1 of =/tmp/floppy-linux/initrd. img

# File initrd. img

Initrd. img: Linux rev 1.0 ext2 filesystem data

Use the loop device to re-mount it to the file system:

# Mount-o loop initrd. img/mnt/ram/

View the content in/mnt/ram, which is exactly the same as that in/tmp/floppy-linux /.

# Ls/mnt/ram

Bin dev etc lost + found mnt proc sbin tmp var

# Umount/mnt/ram

Compress initrd. img impression files

# Gzip-v9 initrd. img

Initrd. img: 90.1% -- replaced with initrd.img.gz

View the compressed size:

# Ls-lh initrd.img.gz

406 K


5. Compile the linux Kernel

# Cp linux-2.4.20.bz2/usr/src/

# Cd/usr/src

# Tar xfvj linux-2.4.20.bz2

# Ln-s linux-2.4.20 linux

Go to the linux source code directory:

# Cd linux

Clear source code tree:

# Make mrproper

Run the configuration program:

# Make menuconfig


Code maturity level options

Select N first. If you have configured the regular items and want to add framebuffer support, select Y. If you do not select Y in code maturity level options, you cannot configure framebuffer.

Loadable module support

Select N. In order to simplify system creation, I do not select support for loading kernel modules in this project.

Processor type and features

Select worker CPU in processor family

Select N for all other options.

General setup

Networking support select Y

Select Y for PCI support

System V ipc select Y

Select Y for systrl support

Kernel support for ELF select Y

You can select N for other content,

Chnology devices (MTD)

Parallel port support

Plug and Play configuration

Select N for all the preceding three items.

Block devices

Normal floppy disk support

Loopback device support

RAM disk support

Initial RAM disk (initrd) support

Per partition statics in/proc/partitions

Select Y for the preceding items, and N for all others.

Multi-device support (RAID and LVM)

Cryptography support (CryptoAPI)

Select N for all the two items

Networking options

In this project, you only need to compile the following items into the kernel:

Packet socket: mmapped IO

TCP/IP networking

Telephony Support select N

ATA/IDE/MFM/RLL support

Select Y, and then the 'ide, ATA, and ATAPI Block devices' button will be activated.

Select Y for the following items, and the rest can be N.

Enhanced IDE/MFM/RLL disk/cdrom/tape/floppy support

Include IDE/ATA-2 DISK support

Auto-Geometry Resizing support

Include IDE/ata cdrom support


SCSI support

Fusion MPT device support

IEEE 1394 (FireWire) support

I2O device support

Select N for all

Network device support

Select Y

Click Ethernet (10 or 100 Mbit) and select the NIC Driver (Reltek8139)

Amateur Radio support

IrDA (infrared) support

ISDN subsystem

The Old CD-ROM drivers (not SCSI, not IDE)

Input core support

Select N for all

Charcter devices

Except Virtual terminal and Support for console on terminal, select N

Multimedia devices

Crypto Hardware support

Select N.

File sytems

Three of them are selected:

/Proc file system support.

Second extended fs support basic file system of BabyLinux.

CD for ISO 9660 CDROM filesytem support.

Console drivers

. Select Y for all the first three,

The Frame-buffer support button is gray and cannot be selected. Don't worry. Return to the first major option:

Code maturity level options select Y to activate this button.

Select Y for the following options:

Support for framebuffer devices

Vesa vga graphics console

Support only 8 pixels wide fonts

Select N for all the remaining items.

Save and exit. The configuration program will automatically generate a hidden configuration file. config


# Make dep

# Make bzImage

BzImage is 654 K


6. Integrated boot disk

# Cp bzImage/mnt/floppy/boot

# Cp/tmp/floppy-linux/initrd.img.gz/mnt/floppy

All files (folders) are as follows:


/Lost + found/

/Boot/

/Boot/grub/

/Boot/grub/stage1

/Boot/grub/stage2

/Boot/grub/menu. lst

/Boot/grub. conf

/Boot/bzImage

/Initrd.img.gz


5. problems encountered in the experiment and summary

1. When creating the boot disk, run the grub command to go To the grub interface and run:

Grub> setup (fd0)

The result may sometimes be an error. It may be a problem with the floppy disk.

2. After a floppy disk is created, restart the machine. An error may occur when grub starts to boot:

Error 16: Inconsistent filesystem strutwre

This is also a problem with floppy disks.

3, in the compilation of the kernel, sometimes may not pass, in Redhet9.0 (kernel-2.4.20) with the gcc-3.3.3 can be compiled through the 2.4.20 version of the kernel, but in the Fedora Core 2 with gcc-3.4.2 will not work, may be the gcc version problem.