CentOS 6 boot分区被删除了恢复总结

CentOS 6系统/boot分区被删除了，但是又不想重新安装系统，下面介绍一种快速的方法恢复boot分区。

1.首先利用centos6镜像进入linux rescue救援模式。

2.启动sshd服务，查看eth0获取的ip地址,然后用ssh secure shell 连接。

SSH Secure Shell 3.2.9 (Build 283)
Copyright (c) 2000-2003 SSH Communications Security Corp - http://www.ssh.com/

This copy of SSH Secure Shell is a non-commercial version.
This version does not include PKI and PKCS #11 functionality.

[root@localhost ~]# cd /boot //进入/boot分区

[root@localhost boot]# ls //查看boot分区的内容
config-2.6.32-71.el6.i686         symvers-2.6.32-71.el6.i686.gz
grub                              System.map-2.6.32-71.el6.i686
initramfs-2.6.32-71.el6.i686.img  vmlinuz-2.6.32-71.el6.i686

[root@localhost boot]# cd ..//返回上层目录

[root@localhost /]# rm -rf /boot/*//删除/boot分区所有内容

[root@localhost /]# ls /boot//查看/boot分区内容为空

[root@localhost /]# mount /dev/sr0 /mnt//挂载cdrom设备到/mnt目录下

mount: block device /dev/sr0 is write-protected, mounting read-only

[root@localhost /]# rpm -ivh /mnt/Packages/kernel-2.6.32-71.el6.i686.rpm --root=/ --force //安装光盘的kernel软件包
Preparing...                ########################################### [100%]
   1:kernel                 ########################################### [100%]

[root@localhost /]# ls /boot //查看/boot分区内容

config-2.6.32-71.el6.i686         System.map-2.6.32-71.el6.i686
initramfs-2.6.32-71.el6.i686.img  vmlinuz-2.6.32-71.el6.i686
symvers-2.6.32-71.el6.i686.gz

[root@localhost /]# mkdir /boot/grub//在/boot目录新建一个grub目录

[root@localhost /]# touch /boot/grub/grub.conf//新建一个grub.conf配置文件

[root@localhost /]# cp -rf /usr/share/grub/i386-pc/* /boot/grub/ //把/usr/share/grub/i386-pc的所有内容拷贝到/boot/grub中。

[root@localhost /]# ls /boot//查看/boot分区内容
config-2.6.32-71.el6.i686         symvers-2.6.32-71.el6.i686.gz
grub                              System.map-2.6.32-71.el6.i686
initramfs-2.6.32-71.el6.i686.img  vmlinuz-2.6.32-71.el6.i686

[root@localhost /]# ls /boot/grub/ //查看/boot/grub目录内容
e2fs_stage1_5  iso9660_stage1_5   stage1           vstafs_stage1_5
fat_stage1_5   jfs_stage1_5       stage2           xfs_stage1_5
ffs_stage1_5   minix_stage1_5     stage2_eltorito
grub.conf      reiserfs_stage1_5  ufs2_stage1_5

[root@localhost /]# fdisk -l //查看分区

Disk /dev/sda: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000b1db4

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          13      102400   83  Linux//这个为/boot启动分区
Partition 1 does not end on cylinder boundary.
/dev/sda2              13         144     1048576   82  Linux swap / Solaris
Partition 2 does not end on cylinder boundary.
/dev/sda3             144        2611    19819520   83  Linux //这个为/根分区

[root@localhost /]# mount//查看所有挂载分区
/dev/sda3 on / type ext4 (rw)//根分区
/dev/sda1 on /boot type ext4 (rw)//boot分区为sda1
devpts on /dev/pts type devpts (rw)
tmpfs on /dev/shm type tmpfs (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
/dev/sr0 on /mnt type iso9660 (ro)

[root@localhost /]# grub//启动grub
Probing devices to guess BIOS drives. This may take a long time.

    GNU GRUB  version 0.97  (640K lower / 3072K upper memory)

 [ Minimal BASH-like line editing is supported.  For the first word, TAB
   lists possible command completions.  Anywhere else TAB lists the possible
   completions of a device/filename.]
grub> root (hd0,0) //首先find /grub/stage1查看/boot分区为(hd0,0)
root (hd0,0)//设置/boot分区为/dev/sda1
 Filesystem type is ext2fs, partition type 0x83
grub> setup (hd0)//重新安装grub
setup (hd0)
 Checking if "/boot/grub/stage1" exists... no
 Checking if "/grub/stage1" exists... yes
 Checking if "/grub/stage2" exists... yes
 Checking if "/grub/e2fs_stage1_5" exists... yes
 Running "embed /grub/e2fs_stage1_5 (hd0)"...  26 sectors are embedded.
succeeded
 Running "install /grub/stage1 (hd0) (hd0)1+26 p (hd0,0)/grub/stage2 /grub/grub.conf"... succeeded
Done.
grub> quit//退出