裁剪RHEL 5.x和RHEL 6.x
写在前面，这篇博文只能让裁剪的系统能够使用简单的bash命令
在裁剪系统之前，先了解能启动系统时，所必需的文件和程序。
1、开机所必需的的bootloader(grub)
2、内核文件、内核镜像文件
3、能执行/sbin/init、有一个能执行命令的bash环境
4、能执行命令时所需的库文件
5、有inittab文件、rc.sysinit执行脚本文件
RHEL 5.x的裁剪
先添加一块硬盘，把裁剪的系统放到新添加的硬盘上，然后用这块新添加的硬盘当启动盘，能够实现裁剪系统的正常启动，则表示裁剪成功。本实验是用vmworkstation虚拟机完成的。
1）添加硬盘，分两个区，一个boot，一个根文件(rootfs)
添加硬盘步骤：VM--->Settings--->Add--->Hard Disk--->next--->Create a new virtual disk--->next---SCSI--->next--->
添加磁盘后重启电脑，然后对磁盘分区。
[[email protected] ~]# fdisk /dev/sdb Command (m for help): n Command action e extended p primary partition (1-4) p Partition number (1-4): 1 First cylinder (1-2610, default 1): Using default value 1 Last cylinder or +size or +sizeM or +sizeK (1-2610, default 2610): +30M Command (m for help): n Command action e extended p primary partition (1-4) p Partition number (1-4): 2 First cylinder (6-2610, default 6): Using default value 6 Last cylinder or +size or +sizeM or +sizeK (6-2610, default 2610): +200M Command (m for help): w [[email protected] ~]#partprobe [[email protected] ~]#mkfs -t ext3 /dev/sdb1 &>/dev/null [[email protected] ~]#mkfs -t ext3 /dev/sdb2 &>/dev/null
2)为新添加的磁盘的第一个分区创建grub文件
3）copy内核文件和生成内核镜像文件
[[email protected] opt]# pwd /opt [[email protected] opt]#find . | cpio -H newc --quiet -o |gzip -9 > /mnt/boot/initrd.gz #把opt目录的所有文件利用cpio打包，然后用gzip命令压缩后，输出到/mnt/boot目录下，文件名为initrd.gz
4）复制init和bash等其它命令以及命令的库文件到新添加硬盘的sysroot目录
思路：复制命令时，命令如果要执行，需要依赖该命令所需的库文件，所有在复制命令时，必须把命令依赖的库文件也复制到相应的目录，init的命令位于/sbin/init，库文件位于/lib64(系统为x86_64)下，要将/sbin/init 复制到新硬盘的/mnt/sysroot/sbin目录下，init所依赖的库，也应该复制/mnt/sysroot/lib64目录下
#!/bin/bash
DestDir=/mnt/sysroot
bincp() {
[ -d ${DestDir}${CmdDir} ] || mkdir -p ${DestDir}${CmdDir}
[ ! -f ${DestDir}${Cmd} ] && cp $Cmd ${DestDir}${Cmd} && echo "copy $Cmd command to $DestDir finished."
}
libcp() {
for Lib in `ldd $Cmd | grep -o "[^[:space:]]*/lib[^[:space:]]*"`;do
LibDir=${Lib%/*}
[ -d ${DestDir}${LibDir} ] || mkdir -p ${DestDir}${LibDir}
[ ! -f ${DestDir}${Lib} ] && cp $Lib ${DestDir}${Lib} && echo "copy $Lib to $DestDir finished."
done
}
read -p "input a command:" Cmd
while [ $Cmd != 'q' -a $Cmd != 'Q' ];do
Cmd=`which $Cmd | grep -v "alias" | sed '[email protected][[:space:]]@@g'`
CmdDir=${Cmd%/*}
bincp
libcp
read -p "input a command:" Cmd
done
printf "=======Copy command is OK=========\n"
脚本的内容
5)建立系统所需的文件和脚本 grub配置文件、inittab文件和rc.sysinit脚本文件
#grub配置文件
cat >> /mnt/boot/grub/grub.conf <<EOF
default=0
timeout=6
title My Litter Linux (RHEL 5.x)
root (hd0,0)
kernel /vmlinuz
initrd /initrd.gz
EOF
#inittab文件
cat >> /mnt/sysroot/etc/inittab << EOF
id:3:initdefault:
si::sysinit:/etc/rc.d/rc.sysinit
EOF
#rc.sysinit脚本文件，/bin/bash，表示开机自动运行bash，生成一个bash环境
cat >> /mnt/sysroot/etc/rc.d/rc.sysinit <<EOF
#!/bin/bash
echo -e "\033[31m Welcome My Little RHEL 5.x\033[0m"
/bin/bash
EOF
chmod +x /mnt/sysroot/etc/rc.d/rc.sysinit
把系统关机，然后把新添加的硬盘作为一个裁剪的系统看能否启动
在虚拟机里面新建一个虚拟机，安装之前裁剪的系统，看是否能正常运行
RHEL 5.x的裁剪的脚本，该脚本能自动化的完成上述的操作
#!/bin/bash
echo -e "\033[31m=======Frist:Formatting a disk partition======\033[0m"
echo "Inital a disk..."
echo -e "\033[31m Warning:\033[0m"
fdisk -l 2>/dev/null | grep -o "^Disk /dev/[sh]d[a-z]"
read -p "Pls choice a disk:" DiskPart
if [ "$DiskPart" == 'quit' ];then
echo "you choice quit."
exit 3
fi
until fdisk -l 2>/dev/null | grep -o "^Disk /dev/[sh]d[a-z]" | grep "^Disk $DiskPart"&>/dev/null ;do
read -p "you choice is wrong,choice again:" DiskPart
done
read -p "Your choice will destory all data,continue:" Choice
until [ $Choice == 'y' -o $Choice == 'n' ];do
read -p "Your choice will destory all data,continue:" Choice
done
if [ $Choice == 'n' ];then
echo "you Choice quit."
exit 4
else
dd if=/dev/zero of=$DiskPart bs=512 count=1 &>/dev/null
sync
sync
sleep 3
echo 'n
p
1 #后面有一行空格
+30M
n
p
2 #后面有一行空格
+200M
w'| fdisk $DiskPart &>/dev/null
fi
partprobe
mkfs -t ext3 ${DiskPart}1 &>/dev/null
mkfs -t ext3 ${DiskPart}2 &>/dev/null
printf "===============Partition is OK=========\n" #以上是分区的脚本
echo -e "\033[31m=======Second:Mount the Partition======\033[0m"
[ -d /mnt/boot ] || mkdir -p /mnt/boot
[ -d /mnt/sysroot ] || mkdir -p /mnt/sysroot
if mount | grep "/dev/sdb1" &>/dev/null;then
echo "/dev/sdb1 is mounted..."
else
mount /dev/sdb1 /mnt/boot
fi
if mount | grep "/dev/sdb2" &>/dev/null;then
echo "/dev/sdb2 is mounted...."
else
mount /dev/sdb2 /mnt/sysroot
fi
printf "===============Mount is OK=========\n"
echo -e "\033[31m=======Third: Create boot partition======\033[0m"
[ -d /mnt/boot/grub ]|| grub-install --root-directory=/mnt /dev/sdb &>/dev/null;echo "grub is ok"
printf "========Boot partition is OK============\n"
echo -e "\033[31m=======Fourth:Copy the kernel and make the kernel p_w_picpath file======\033[0m"
cp /boot/vmlinuz-2.6.18-308.el5 /mnt/boot/vmlinuz
rm -rf /opt/*
cd /opt
mkinitrd /opt/initrd-`uname -r`.img `uname -r`
zcat /opt/initrd-`uname -r`.img | cpio -id &>/dev/null
rm -rf /opt/initrd-`uname -r`.img
sed -i '/resume/[email protected]@#[email protected]' /opt/init #把resume那行的前面添加#，即注释掉resume开头的行
sed -i 's/mkrootdev/# &/' /opt/init #先把mkrootdev开头的行注释
sed -i '/mkrootdev/a\mkrootdev -t ext3 -o defaults,ro /dev/sda2' /opt/init #然后在mkrootdev那行下面添加一行mkrootdev -t ext3 -o defaults,ro /dev/sda2
find . | cpio -H newc --quiet -o |gzip -9 > /mnt/boot/initrd.gz
printf "========Kernel and kernel p_w_picpath file is OK========\n"
echo -e "\033[31m=======Fifth:Edit grub configuration file======\033[0m"
cat >> /mnt/boot/grub/grub.conf <<EOF
default=0
timeout=6
title My Litter Linux (RHEL 5.x)
root (hd0,0)
kernel /vmlinuz
initrd /initrd.gz
EOF
printf "=========Grub configuration file is OK========\n"
mkdir -p /mnt/sysroot/{proc,sys,dev,etc/rc.d,lib/modules,bin,sbin,home,var,tmp}
echo -e "\033[31m=======Sixth:Copy system running program=====\033[0m"
echo -e "\033[31m You can input this command\033[0m"
cat << EOF
init
bash
lsmod
insmod
cp
mv
ls
vim
cat
EOF
DestDir=/mnt/sysroot
bincp() {
[ -d ${DestDir}${CmdDir} ] || mkdir -p ${DestDir}${CmdDir}
[ ! -f ${DestDir}${Cmd} ] && cp $Cmd ${DestDir}${Cmd} && echo "copy $Cmd command to $DestDir finished."
}
libcp() {
for Lib in `ldd $Cmd | grep -o "[^[:space:]]*/lib[^[:space:]]*"`;do
LibDir=${Lib%/*}
[ -d ${DestDir}${LibDir} ] || mkdir -p ${DestDir}${LibDir}
[ ! -f ${DestDir}${Lib} ] && cp $Lib ${DestDir}${Lib} && echo "copy $Lib to $DestDir finished."
done
}
read -p "input a command:" Cmd
while [ $Cmd != 'q' -a $Cmd != 'Q' ];do
Cmd=`which $Cmd | grep -v "alias" | sed '[email protected][[:space:]]@@g'`
CmdDir=${Cmd%/*}
bincp
libcp
read -p "input a command:" Cmd
done
printf "=======Copy command is OK=========\n"
echo -e "\033[31m=======Seventh:Create inittab file and rc.sysinit script file======\033[0m"
cat >> /mnt/sysroot/etc/inittab << EOF
id:3:initdefault:
si::sysinit:/etc/rc.d/rc.sysinit
EOF
cat >> /mnt/sysroot/etc/rc.d/rc.sysinit <<EOF
#!/bin/bash
echo -e "\033[31m Welcome My Little RHEL 5.x\033[0m"
/bin/bash
EOF
chmod +x /mnt/sysroot/etc/rc.d/rc.sysinit
sync
sync
sync
sync
运行脚本的过程
RHEL 6.x系统的裁剪步骤就详细描述了，直接写脚本
#!/bin/bash
echo -e "\033[31m=======Frist:Formatting a disk partition======\033[0m"
echo "Inital a disk..."
echo -e "\033[31m Warning:\033[0m"
fdisk -l 2>/dev/null | grep -o "^Disk /dev/[sh]d[a-z]"
read -p "Pls choice a disk:" DiskPart
if [ "$DiskPart" == 'quit' ];then
echo "you choice quit."
exit 3
fi
until fdisk -l 2>/dev/null | grep -o "^Disk /dev/[sh]d[a-z]" | grep "^Disk $DiskPart"&>/dev/null ;do
read -p "you choice is wrong,choice again:" DiskPart
done
read -p "Your choice will destory all data,continue:" Choice
until [ $Choice == 'y' -o $Choice == 'n' ];do
read -p "Your choice will destory all data,continue:" Choice
done
if [ $Choice == 'n' ];then
echo "you Choice quit."
exit 4
else
dd if=/dev/zero of=$DiskPart bs=512 count=1 &>/dev/null
sync
sync
sleep 3
echo 'n
p
1
+30M
n
p
2
+200M
w'| fdisk $DiskPart &>/dev/null
fi
partx -a ${DiskPart}1 $DiskPart
partx -a ${DiskPart}2 $DiskPart
mkfs -t ext4 ${DiskPart}1 &>/dev/null
mkfs -t ext4 ${DiskPart}2 &>/dev/null
printf "===============Partition is OK=========\n"
echo -e "\033[31m=======Second:Mount the Partition======\033[0m"
[ -d /mnt/boot ] || mkdir -p /mnt/boot
[ -d /mnt/sysroot ] || mkdir -p /mnt/sysroot
if mount | grep "/dev/sdb1" &>/dev/null;then
echo "/dev/sdb1 is mounted..."
else
mount /dev/sdb1 /mnt/boot
fi
if mount | grep "/dev/sdb2" &>/dev/null;then
echo "/dev/sdb2 is mounted...."
else
mount /dev/sdb2 /mnt/sysroot
fi
printf "===============Mount is OK=========\n"
echo -e "\033[31m=======Third: Create boot partition======\033[0m"
[ -d /mnt/boot/grub ]|| grub-install --root-directory=/mnt /dev/sdb &>/dev/null;echo "grub is ok"
printf "========Boot partition is OK============\n"
echo -e "\033[31m=======Fourth:Copy the kernel and make the kernel p_w_picpath file======\033[0m"
cp /boot/vmlinuz-2.6.32-358.el6.x86_64 /mnt/boot/vmlinuz
mkinitrd /opt/initramfs-`uname -r`.img `uname -r`
cp /opt/initramfs-2.6.32-358.el6.x86_64.img /mnt/boot/initrd.gz
printf "========Kernel and kernel p_w_picpath file is OK========\n"
echo -e "\033[31m=======Fifth:Edit grub configuration file======\033[0m"
cat >> /mnt/boot/grub/grub.conf <<EOF
default=0
timeout=6
title My Litter Linux (RHEL 6.x)
root (hd0,0)
kernel /vmlinuz ro root=/dev/sda2
initrd /initrd.gz
EOF
printf "=========Grub configuration file is OK========\n"
mkdir -p /mnt/sysroot/{proc,sys,dev,etc/rc.d,lib/modules,bin,sbin,home,var,tmp}
echo -e "\033[31m=======Sixth:Copy system running program=====\033[0m"
echo -e "\033[31m You can input this command\033[0m"
cat << EOF
init
bash
lsmod
insmod
cp
mv
ls
vim
cat
EOF
DestDir=/mnt/sysroot
bincp() {
[ -d ${DestDir}${CmdDir} ] || mkdir -p ${DestDir}${CmdDir}
[ ! -f ${DestDir}${Cmd} ] && cp $Cmd ${DestDir}${Cmd} && echo "copy $Cmd command to $DestDir finished."
}
libcp() {
for Lib in `ldd $Cmd | grep -o "[^[:space:]]*/lib[^[:space:]]*"`;do
LibDir=${Lib%/*}
[ -d ${DestDir}${LibDir} ] || mkdir -p ${DestDir}${LibDir}
[ ! -f ${DestDir}${Lib} ] && cp $Lib ${DestDir}${Lib} && echo "copy $Lib to $DestDir finished."
done
}
read -p "input a command:" Cmd
while [ $Cmd != 'q' -a $Cmd != 'Q' ];do
Cmd=`which $Cmd | grep -v "alias" | sed '[email protected][[:space:]]@@g'`
CmdDir=${Cmd%/*}
bincp
libcp
read -p "input a command:" Cmd
done
printf "=======Copy command is OK=========\n"
echo -e "\033[31m=======Seventh:Create inittab file and rc.sysinit script file======\033[0m"
cat >> /mnt/sysroot/etc/inittab << EOF
id:3:initdefault:
EOF
cat >> /mnt/sysroot/etc/rc.d/rc.sysinit <<EOF
#!/bin/bash
echo -e "\033[31m Welcome My Little RHEL 6.x\033[0m"
/bin/bash
EOF
chmod +x /mnt/sysroot/etc/rc.d/rc.sysinit
sync
sync
sync
sync
转载于:https://blog.51cto.com/litaotao/1266771