linux基础之Mini Linux制作
一、编译一个简单的linux步骤如下：
# yum groupinstall ""Development Tools" "Server Platform Development" -y //安装开发包组 # tar xf linux-3.10.65.tar.xz //下载内核这里就不介绍了 # cd /usr/src # ln -sv linux-3.10.15 linux # cd linux # make help
# make allnoconfig
# make menuconfig
这里简单介绍下这次编译到的选项：
内核核心模块相关的：
[*]64-bit kernel //内核编译成64位的
[*]enable loadable module support --> [*]Module uploading //允许装卸载模块，这里都是编译进内核的，不借助ramdisk装载模块，先选中吧
Processor type and features ---> [*]Symmetric multi-processing support //支持多处理器，linux上多处理器和多核心是一个意思
Processor family (Generic-x86-64) ---> (X) Generic-x86-64 //选通用的就可以
Bus options (PCI etc.) ---> [*] PCI support //PCI相关的
Device Drivers ---> SCSI device support ----> [*]SCSI device support //SCSI设备的支持
[*]SCSI disk support //SCSI硬盘支持
[*] Fusion MPT device support ---> [*] Fusion MPT ScsiHost drivers for SPI //lspci命令可以查看到本机pci的信息
(*) Fusion MPT misc device (ioctl) drivers
文件系统相关的：
File systems ---> <*> Second extended fs support
<*> Ext3 journalling file system support
[*] Default to 'data=ordered' in ext3 (NEW)
[*] Ext3 extended attributes (NEW)
<*> The Extended 4 (ext4) filesystem
Executable file formats / Emulations ---> [*] Kernel support for ELF binaries
[*] Write ELF core dumps with partial segments (NEW)
<*> Kernel support for scripts starting with #!
键盘鼠标usb相关的：
Device Drivers ---> Input device support ---> [*]Keyboards --->
[*] Mice --->
<*> Mouse interface
[*] USB support ---> <*> Support for Host-side USB
<*> xHCI HCD (USB 3.0) support
<*> EHCI HCD (USB 2.0) support
<*> OHCI HCD support
<*> UHCI HCD (most Intel and VIA) Support
udev相关的：
SRE实战 互联网时代守护先锋，助力企业售后服务体系运筹帷幄！一键直达领取阿里云限量特价优惠。Device Drivers --> Generic Driver Options --> Mintain a devtmpfs filesystem to mount at /dev //识别到的设备都挂载到/dev目录
[*] Automount devtmpfs at /dev, after the kernel mounted the rootfs
# make -j 4 bzImage //只编译内核文件
# fdisk /dev/sdb //在现有系统上添加一块盘，分两个区，一个用来做boot，一个用来做根目录 # mke2fs -t ext4 /dev/sdb1 # mke2fs -t ext4 /dev/sdb2 # mkdir /mnt/{boot,sysroot}
# mkdir -pv etc dev proc sys bin usr/{lib,bin,sbin,lin64} lib64 lib/modules home var/{log,run,lock} tmp mnt media root # mount /dev/sdb1 /mnt/boot/ # mount /dev/sdb2 /mnt/sysroot
# grub-install --root-directory=/mnt /dev/sdb
# cd /usr/src/linux
# cp arch/x86/boot/bzImage /mnt/boot/bzImage
# file /mnt/boot/bzImage
# vim /mnt/boot/grub/grub.conf
default=0
timeout=5
title Mini Linux (3.10.67)
root (hd0,0)
kernel /bzImage ro root=/dev/sda2 init=/bin/bash
写一个脚本bincp复制命令及依赖库到sysroot下
#!/bin/bash
#
target=/mnt/sysroot
[ -d $target ] || mkdir /mnt/sysroot
read -p "A command:" command
libcp(){
for lib in $(ldd $1 | grep -o "[^[:space:]]*/lib[^[:space:]]*"); do
libdir=$(dirname $lib)
[ -d $target$libdir ] || mkdir -p $target$libdir
[ -f $target$lib ] || cp $lib $target$lib
done
}
while [ "$command" != 'q' -a "$command" != 'quit' ]; do
if !which $command &> /dev/null;then
read -p "No such command,enter again:" command
continue
fi
command=$(which --skip-alias $command)
cmnddir=$(dirname $command)
[ -d $target$cmnddir ] || mkdir -p $target$cmnddir
[ -f $target$command ] || cp $command $target$command
libcp $command
read -p "Another command(quit):" command
done
新建虚拟机Mini Linux使用上面的sdb硬盘
重启Mini Linux，可以在bash命令行进行一些命令的操作，比如cd,ls,mount等
也可以新建init程序让系统开机运行
新建脚本init： /mnt/sysroot/sbin/init
#!/bin/bash
#
echo -e "\twelcome to \033[32mMini\033[0m linux"
mount -n -t proc proc /proc
mount -n -t sysfs /sys
mount -n -o remount,rw /dev/sda2 /
/bin/bash
# chmod +x /mnt/sysroot/sbin/init
二、结合busybox+dropbear制作linux
静态编译busybox:
下载busybox：https://busybox.net/downloads/
# wget https://busybox.net/downloads/
# tar xf busybox-1.22.1.tar.bz2 # cd busybox-1.22.1 # yum install glibc-static //静态编译busybox依赖到的库
# make menuconfig //配置下面两项，其他默认就可以了
Busybox Settings ---> Build Options ---> [*] Build BusyBox as a static binary (no shared libs)
Installation Options ("make install" behavior) ---> What kind of applet links to install (as soft-links) ---> (X) as soft-links //安装完成后文件链接类型
(./_install) BusyBox installation prefix (NEW) //安装完成在什么位置，默认当前编译路径下，默认就好
# make && make install //安装busybox
# cd /mnt/sysroot
# rm -rf ./* //删掉之前在sysroot中创建的目录,busybox会自动创建
# cd busybox-1.22.1
# tree _install //可以看一下busybox安装后生成了哪些文件
# cp -a _install/* /mnt/sysroot/ //复制_install中所有文件到sysroot中
# cd /mnt/sysroot
# rm linuxrc //删掉busybox模拟的init程序,"ls /sbin | grep init"中的init就够用了
修改grub配置文件：
default=0
timeout=3
title Mini Linux (3.10.67)
root (hd0,0)
kernel /bzImage ro root=/dev/sda2 init=/sbin/init //修改init就好
# mkdir -pv etc lib lib64 proc sys dev root home boot mnt media tmp var //在sysroot下创建其他缺少的目录
busybox默认模拟的是CentOS5的init程序，它会去读取inittab文件，所以我们创建一个/sysroot/etc/inittab,内容如下：
# vim /sysroot/etc/inittab
::sysinit:/etc/rc.d/rc.sysinit //完成系统初始化 tty1::askfirst:/bin/sh //启动几个终端
tty2::askfirst:/bin/sh
tty3::askfirst:/bin/sh
tty4::askfirst:/bin/sh ::ctrlaltdel:/sbin/reboot //ctrl+alt+del组合键就重启 ::shutdown:/bin/umount -a -r //关机前卸载所有文件系统
接下来创建初始化脚本：/sysroot/etc/rc.d/rc.sysinit
#!/bin/sh
#
echo -e "\tWelcome to \033[32mMini\033[0m Linux"
mount -t proc porc /proc //如果不能挂载，换成绝对路径
mount -t sysfs sysfs /sys
echo "scan /sys and to populatte to /dev..."
mdev -s //系统启动时自动输出所有文件到/dev目录下
mount -o remount,rw /dev/sda2 /
echo "mouting all filesystems.."
mount -a //挂载剩余的所有文件系统
# chmod +x etc/rc.d/rc.sysinit
将网络相关功能编译进内核：
# cd /usr/src/linux
# make menuconfig
-*- Networking support ---> Networking options ---> [*] TCP/IP networking
[*] IP: multicasting
[*] IP: advanced router
[*] IP: kernel level autoconfiguration
Device Drivers --->[*] Network device support ---> [*] Ethernet driver support (NEW) --->[*] Intel devices (NEW)
<*> Intel(R) PRO/1000 Gigabit Ethernet support
# make bzImage
# cp arch/x86/boot/bzImage /mnt/boot
重启Mini Linux测试网络功能
# ifconfig -a //查看网卡 # ifconfig eth0 192.168.2.20 up # ifconfig lo 127.0.0.1 up
# ping 192.168.2.1
假设把上面的网络功能编译为模块
Device Drivers --->[*] Network device support ---> [*] Ethernet driver support (NEW) ---> <M> Intel(R) PRO/1000 Gigabit Ethernet support
# cp arch/x86/boot/bzImage /mnt/boot
# sync
编译网卡e1000,将.ko文件复制到/mnt/sysroot/lib/modules下
# cd /usr/src/linux
# make M=drivers/net/ethernet/intel/e1000
# mkdir /mnt/sysroot/lib/modules -pv
# cp drivers/net/ethernet/intel/e1000/e1000.ko /mnt/sysroot/lib/modules/
重启Mini Linux，装载进e1000网卡模块
# insmod /lib/modules/e1000.ko
设置系统初始化的时候加载网卡模块，并初始化
# vim /etc/rc.d/rc.sysinit
echo "Load driver for e1000..." insmod /lib/modules/e1000.ko echo "Initializing ethernet card..." ifconfig eth0 192.168.2.20 up ifconfig lo 127.0.0.1 up [ -f /etc/sysconfig/network ] && . /etc/sysconfig/network [ -z "$HOSTNAME" -o "$HOSTNAME" == '(none)' ] && HOSTNAME='lcoalhost' hostname $HOSTNAME
设置主机名
# mkdir etc/sysconfig
# vim etc/sysconfig/network
HOSTNAME=mini.alen.com
给Mini Linux添加账号和密码
# vim etc/passwd root:x:0:0::/root:/bin/bash
# vim etc/group
root:x:0:
# vim etc/shadow
或者直接追加宿主机上的：# head -1 /etc/shadow > etc/shadow
# chmod 400 etc/shadow
sha密码可能不支持，换成md5的吧
# openssl passwd -1 -salt $(openssl rand -hex 4)
添加模拟终端：
修改etc/initab文件：
# vim etc/insttab
::sysinit:/etc/rc.d/rc.sysinit
::respawn:/sbin/getty 9600 tty1 //修改这几个模拟终端，getty开机时会自动调用login程序
::respawn:/sbin/getty 9600 tty2 //
::respawn:/sbin/getty 9600 tty3 //
::ctrlaltdel:/sbin/reboot
::shutdown:/bin/umount -a -r
添加issue文件，修改终端显示信息
# vim etc/issue
Welcome to alen Linux
Kernel \r
添加ssh服务
下载dropbear源码：https://matt.ucc.asn.au/dropbear/releases/dropbear-2019.78.tar.bz2
默认编译安装就可以了
复制dropbear命令到sysroot下
# bash bincp.sh
dropbear,dropbearkey,dbclient //添加这几个就可以了
添加存放远程终端文件的目录dev/pts
# mkdir dev/pts
# vim etc/fstab
devpts /dev/pts devpts mode=620 0 0 //挂载pts
为dropbear生成密钥文件
# mkdir etc/dropbear
# cd etc/dropbear
# dropbearkey -t rsa -s 2048 -f dropbear_rsa_host_key
# dropbearkey -t dss -f dropbear_dss_host_key
添加安全shell
# vim etc/shells
比如： /bin/sh /bin/ash /bin/hush /bin/bash /sbin/nologin
添加nsswitch服务：网络服务转换
# vim etc/nsswitch.conf
passwd: files
group: files
shadow: files
hosts: files dns
复制nsswitch的库文件到sysroot下
# mkdir usr/lib64
# cp -d /lib64/libnss_files* lib64/
# cp -d /usr/lib64/libnss3.so usr/lib64/
# cp -d /usr/lib64/libnssutil3.so usr/lib64/
# cp -d /usr/lib64/libnss_files* usr/lib64/
重启Mini Linux，测试
# vim .bash_profile
设置PS1环境变量 export PS1='[\u@\h \w]\$'
export PATH=$PATH:/usr/local/bin:/usr/local/sbin
添加dropbear的pid存放路径
# mkdir /var/run
# dropbear -F -E //让dropbear工作于前台
# mkdir /dev/pts
# mount -t devpts devpts /dev/pts
# vi /etc/profile
[ $UID -eq 0 ] && export PATH=/bin:/sbin:/usr/bin:/usr/sbin
至此，一个迷你型的linux就编译好了
