服务器评测
一 删除boot目录下的所有文件
#删除/boot，然后重启
[root@serv01 boot]# rm -rf *
[root@serv01 boot]# ls
[root@serv01 boot]# reboot
#会发现出现错误
Error 15
#我们关闭虚拟机，然后使用光盘进行驱动，注意把内存调整为800M；重启计算机，在启动的一瞬间，按ESC键，进入Boot Menu，选择CD-ROM Drive
#进入引导界面，选择Rescueinstalled system，Choose a language，选择English，Keyboad Type选择us，Rescue method选择Local CD/DVD，Setup networking选择no，Rescue选择Contiune，Rescue选择ok，下一个界面再次选择ok，shell start shell，启动shell。
#发现进入的是bash，此时cd /boot是不行的
#输入chroot/mnt/sysimage进入/，然后进入/boot，发现bash变为sh
#配置yum源，
ls
ls /iso
mount /dev/cdrom /iso
#重装内核
yum reinstall kernerl -y
#也可以使用rpm安装 rpm -ivhkenerl-xxx –force –replacefiles
#安装grub
grub-install /dev/sda
#退出sh
exit
#进入bash，然后重启
reboot
#进入grub，依次执行以下内容（按Tab键）
root (hd0,0)
kernel /vmlinuz-2.6.32-131.0.15.el6.x86_64
initrd /initramfs-2.6.32-131.0.15.el6.x86_64.img
boot
#再次进入grub，依次执行以下内容
root (hd0,0)
kernel /vmlinuz-2.6.32-131.0.15.el6.x86_64
initrd/initramfs-2.6.32-131.0.15.el6.x86_64.img
boot
#修复成功，可以编辑grub.conf文件，下次就不重新引导，grub.conf文件如下
[root@serv01 opt]# cd /boot/grub/
[root@serv01 grub]# vim grub.conf
[root@serv01 grub]# cat grub.conf
default=0
timeout=5
title RedHat Server 6.1
root(hd0,0)
kernel/vmlinuz-2.6.32-131.0.15.el6.x86_64 ro root=/dev/sda2
initrd/initramfs-2.6.32-131.0.15.el6.x86_64.img
[root@larrywen /]# ssh 192.168.1.11
root@192.168.1.11’s password:
Last login: Wed Jul 31 18:05:19 2013 from192.168.1.1
#建议把/boot分区放在第一个位置
二 rc.sysinit文件丢失
#rc.sysinit文件丢失，进入修复模式，方法同上，只需重新安装（拷贝）这个文件即可
[root@serv01 grub]# ls /etc/rc.d/rc.sysinit
/etc/rc.d/rc.sysinit
#安装出错
[root@serv01 grub]#yum install/etc/rc.d/rc.sysinit
#重新安装
[root@serv01 grub]#yum reinstall/etc/rc.d/rc.sysinit
[root@serv01 ~]# rpm -qf/etc/rc.d/rc.sysinit
initscripts-9.03.23-1.el6.x86_6
#其他的系统文件丢失，类似操作
接下来请看第2页精彩内容： http://www.linuxidc.com/Linux/2013-08/88574p2.htm
推荐阅读：
Linux系统文件查找命令find的基本使用及其高级用法 http://www.linuxidc.com/Linux/2013-05/84991.htm
Linux Windows等操作系统文件名命名规范 http://www.linuxidc.com/Linux/2012-03/56993.htm
Linux系统文件的位置 http://www.linuxidc.com/Linux/2011-08/40438.htm
Linux系统文件概念和文件类型 http://www.linuxidc.com/Linux/2011-08/40225.htm
三 grub.conf文件被删除
#可以看到/etc/grub.conf/boot/grub/grub.conf是同一个文件
[root@serv01 ~]# ls /etc/grub.conf/boot/grub/grub.conf -l
-rw——-. 1 root root 817 Jul 30 23:47 /boot/grub/grub.conf
lrwxrwxrwx. 1 root root 22 Jul 23 00:57 /etc/grub.conf ->../boot/grub/grub.conf
#删除grub.conf文件后不能引导解决
#第一步，查看磁盘分区
[root@serv01 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 9.7G 1.1G 8.1G 12% /
tmpfs 188M 0 188M 0% /dev/shm
/dev/sda1 194M 25M 160M 14% /boot
/dev/sda5 4.0G 137M 3.7G 4% /opt
/dev/sr0 3.4G 3.4G 0 100% /iso
#进入目录删除grub.conf文件
[root@serv01 ~]# cd /boot/grub/
[root@serv01 grub]# rm -rf grub.conf
[root@serv01 grub]# reboot
#依次输入这些命令
root (hd0,0)
#这一步按住tab键会自动补齐的
kernel /
#然后在后面加上root=/dev/sda2，注意，您的机器不一定是/dev/sda2，您要通过df -h查看根分区是属于哪个分区
kernel /vmlinuz-2.6.32-131.0.15.el6.x86_64ro root=/dev/sda2
#这一步按住tab键也会自动补齐的
initrd /
initrd/initramfs-2.6.32-131.0.15.el6.x86_64.img
#注意，如果有多个内核，需要自行选择
#最后输入boot重启
#重启后，进入boot目录，发现没有生成这个文件
[root@serv01 ~]# cd /boot/grub/
[root@serv01 grub]# ls grub.conf
ls: cannot access grub.conf: No such fileor directory
#下次启动时我们发现还需要重新引导，此时我们重新创建这个文件，输入以下内容即可
#这里有个小技巧，我们在使用vim编辑文件时，在命令模式，可以读入命令，就可以很方便地读取和拷贝（!表示执行命令）
r !ls/boot/initramfs-2.6.32-131.0.15.el6.x86_64.img
[root@serv01 grub]# vim grub.conf
[root@serv01 grub]# cat grub.conf
default=0
timeout=5
title RedHat Server 6.1
root(hd0,0)
kernel/vmlinuz-2.6.32-131.0.15.el6.x86_64 ro root=/dev/sda2
initrd/initramfs-2.6.32-131.0.15.el6.x86_64.img
[root@larrywen grub]# ls
device.map splash.xpm.gz
[root@serv01 grub]# find . -name”*stage*”
./minix_stage1_5
./stage1
./xfs_stage1_5
./ufs2_stage1_5
./ffs_stage1_5
./e2fs_stage1_5
./stage2
./jfs_stage1_5
./iso9660_stage1_5
./vstafs_stage1_5
./fat_stage1_5
./reiserfs_stage1_5
#把带有stage的文件全部删除也不影响，重启仍然正常
[root@serv01 grub]# find . -name”*stage*” |xargs rm -rf {}\;
[root@serv01 grub]# ll
total 8
-rw-r–r–. 1 root root 63 Jul 23 00:57 device.map
-rw-r–r–. 1 root root 170 Jul 31 00:30 grub.conf
lrwxrwxrwx. 1 root root 11 Jul 23 00:57 menu.lst -> ./grub.conf
-rw-r–r–. 1 root root 1341 May 7 2010splash.xpm.gz
四 进入boot目录，删除所有的文件，在不断开连接的情况下恢复
[root@serv01 ~]# cd /boot
[root@serv01 boot]# ls
config-2.6.32-131.0.15.el6.x86_64 initramfs-2.6.32-131.0.15.el6.x86_64.img System.map-2.6.32-131.0.15.el6.x86_64
efi lost+found vmlinuz-2.6.32-131.0.15.el6.x86_64
grub symvers-2.6.32-131.0.15.el6.x86_64.gz
[root@serv01 boot]# rm -rf *
[root@serv01 boot]# ll
total 0
#第一步，安装grub
[root@serv01 boot]# grub-install /dev/sda
Probing devices to guess BIOS drives. Thismay take a long time.
Installation finished. No error reported.
This is the contents of the device map /boot/grub/device.map.
Check if this is correct or not. If any ofthe lines is incorrect,
fix it and re-run the script`grub-install’.
(fd0) /dev/fd0
(hd0) /dev/sda
#第二步，安装kernel
[root@serv01 boot]# yum reinstall kernel -y
Loaded plugins: product-id, subscription-manager
Updating Red Hat repositories.
Setting up Reinstall Process
rhel-iso | 4.0 kB 00:00 …
Resolving Dependencies
–> Running transaction check
—> Package kernel.x86_640:2.6.32-131.0.15.el6 will be installed
–> Finished Dependency Resolution
Dependencies Resolved
======================================================================================================================================
Package Arch Version Repository Size
======================================================================================================================================
Reinstalling:
kernel x86_64 2.6.32-131.0.15.el6 rhel-iso 23 M
Transaction Summary
======================================================================================================================================
Reinstall 1 Package(s)
Total download size: 23 M
Installed size: 108 M
Downloading Packages:
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Installing :kernel-2.6.32-131.0.15.el6.x86_64 1/1
duration: 263(ms)
Installed products updated.
Installed:
kernel.x86_64 0:2.6.32-131.0.15.el6
Complete!
[root@serv01 boot]# ls
config-2.6.32-131.0.15.el6.x86_64 initramfs-2.6.32-131.0.15.el6.x86_64.img System.map-2.6.32-131.0.15.el6.x86_64
grub symvers-2.6.32-131.0.15.el6.x86_64.gz vmlinuz-2.6.32-131.0.15.el6.x86_64
#进入grub目录，然后新建grub.conf文件
[root@serv01 boot]# cd grub/
[root@serv01 grub]# ll
total 268
-rw-r–r–. 1 root root 30 Jul 31 00:44 device.map
-rw-r–r–. 1 root root 13396 Jul 31 00:44 e2fs_stage1_5
-rw-r–r–. 1 root root 12620 Jul 31 00:44 fat_stage1_5
-rw-r–r–. 1 root root 11764 Jul 31 00:44 ffs_stage1_5
-rw-r–r–. 1 root root 11772 Jul 31 00:44 iso9660_stage1_5
-rw-r–r–. 1 root root 13300 Jul 31 00:44 jfs_stage1_5
-rw-r–r–. 1 root root 11956 Jul 31 00:44 minix_stage1_5
-rw-r–r–. 1 root root 14444 Jul 31 00:44 reiserfs_stage1_5
-rw-r–r–. 1 root root 512 Jul 31 00:44 stage1
-rw-r–r–. 1 root root 126040 Jul 31 00:44stage2
-rw-r–r–. 1 root root 12040 Jul 31 00:44 ufs2_stage1_5
-rw-r–r–. 1 root root 11396 Jul 31 00:44 vstafs_stage1_5
-rw-r–r–. 1 root root 13980 Jul 31 00:44 xfs_stage1_5
[root@serv01 grub]# vim grub.conf
#文件内容如下
[root@serv01 grub]# cat grub.conf
default=0
timeout=5
title RedHat Server 6.1
root(hd0,0)
kernel/vmlinuz-2.6.32-131.0.15.el6.x86_64 ro root=/dev/sda2 quiet
initrd/initramfs-2.6.32-131.0.15.el6.x86_64.img
[root@serv01 grub]# reboot
Broadcast message from root@serv01.host.com
(/dev/pts/0)at 0:47 …
The system is going down for reboot NOW!
[root@serv01 grub]# Connection to192.168.1.11 closed by remote host.
Connection to 192.168.1.11 closed.
#重启后然后重新连接，成功，OK！
[root@larrywen Desktop]# ssh 192.168.1.11
root@192.168.1.11’s password:
Last login: Wed Jul 31 00:43:50 2013 from192.168.1.1
[root@serv01 ~]#
