CentOS restore the deleted boot Partition

CentOS restore the deleted boot Partition

In CentOS 6, the boot partition is deleted due to carelessness or operation errors,

In this case, can I restore the deleted boot partition?

1. Use the centos6 image to enter the linux rescue mode.

2. Start the sshd service, view the IP address obtained by eth0, and then connect to it using ssh secure shell.

　　

SSHSecureShell3.2.9（Build283）　　Copyright（c）2000-2003SSHCommunicationsSecurityCorp-http://www.ssh.com/　　ThiscopyofSSHSecureShellisanon-commercialversion.　　ThisversiondoesnotincludePKIandPKCS#11functionality.　　［root@localhost~］# Cd/boot // enter/boot Partition　　［root@localhostboot］# Ls // view the content of the boot Partition　　config-2.6.32-71.el6.i686symvers-2.6.32-71.el6.i686.gz　　grubSystem.map-2.6.32-71.el6.i686　　initramfs-2.6.32-71.el6.i686.imgvmlinuz-2.6.32-71.el6.i686　　［root@localhostboot］# Cd .. // Return to the upper directory　　［root@localhost/］# Rm-rf/boot/* // delete all content in the/boot Partition　　［root@localhost/］# Ls/boot // check/boot partition content is blank　　［root@localhost/］# Mount/dev/sr0/mnt // mount the cdrom device to the/mnt directory　　mount：blockdevice/dev/sr0iswrite-protected，mountingread-only　　［root@localhost/］#rpm-ivh/mnt/Packages/kernel-2.6.32-71.el6.i686.rpm--root=/--

Force // install the disc's kernel package

　

　Preparing.。。###########################################［100%］　　1:kernel###########################################［100%］　　［root@localhost/］# Ls/boot // view/boot partition content　　config-2.6.32-71.el6.i686System.map-2.6.32-71.el6.i686　　initramfs-2.6.32-71.el6.i686.imgvmlinuz-2.6.32-71.el6.i686　　symvers-2.6.32-71.el6.i686.gz　　［root@localhost/］# Mkdir/boot/grub // create a grub directory in the/boot directory　　［root@localhost/］# Touch/boot/grub. conf // create a grub. conf configuration file.　　［root@localhost/］#cp-rf/usr/share/grub/i386-pc/*/boot/grub///

Copy all content from/usr/share/grub/i386-pc to/boot/grub.

　　

［root@localhost/］# Ls/boot // view/boot partition content　　config-2.6.32-71.el6.i686symvers-2.6.32-71.el6.i686.gz　　grubSystem.map-2.6.32-71.el6.i686　　initramfs-2.6.32-71.el6.i686.imgvmlinuz-2.6.32-71.el6.i686　　［root@localhost/］# Ls/boot/grub // view the/boot/grub directory content　　e2fs_stage1_5iso9660_stage1_5stage1vstafs_stage1_5　　fat_stage1_5jfs_stage1_5stage2xfs_stage1_5　　ffs_stage1_5minix_stage1_5stage2_eltorito　　grub.confreiserfs_stage1_5ufs2_stage1_5　　［root@localhost/］# Fdisk-l // view partitions　　Disk/dev/sda：21.5GB，21474836480bytes　　255heads，63sectors/track，2610cylinders　　Units=cylindersof16065*512=8225280bytes　　Sectorsize（logical/physical）：512bytes/512bytes　　I/Osize（minimum/optimal）：512bytes/512bytes　　Diskidentifier：0x000b1db4　　DeviceBootStartEndBlocksIdSystem　　/dev/sda1*11310240083Linux//This is/bootStart Partition　　Partition1doesnotendoncylinderboundary.　　/dev/sda213144104857682Linuxswap/Solaris

　　

Partition2doesnotendoncylinderboundary.　　/dev/sda314426111981952083Linux//This is/root Partition　　［root@localhost/］# Mount // view all mount partitions　　/dev/sda3on/typeext4（rw）//Root Partition　　/dev/sda1on/boottypeext4（rw）//bootThe partition is sda1.　　devptson/dev/ptstypedevpts（rw）　　tmpfson/dev/shmtypetmpfs（rw）　　procon/proctypeproc（rw）　　sysfson/systypesysfs（rw）　　/dev/sr0on/mnttypeiso9660（ro）　　［root@localhost/］# Grub // start grub　　ProbingdevicestoguessBIOSdrives.Thismaytakealongtime.　　GNUGRUBversion0.97（640Klower/3072Kuppermemory）　　［MinimalBASH-likelineeditingissupported.Forthefirstword，TAB　　listspossiblecommandcompletions.AnywhereelseTABliststhepossible　　completionsofadevice/filename.］　　grub》root（hd0，0）//Firstfind/grub/stage1View/bootPartition is (hd0, 0)　　root（hd0，0）//Set/bootPartition is/dev/sda1　　Filesystemtypeisext2fs，partitiontype0x83　　grub》setup（hd0）//Reinstall grub　　setup（hd0）

　

　Checkingif“/boot/grub/stage1”exists.。。no　　Checkingif“/grub/stage1”exists.。。yes　　Checkingif“/grub/stage2”exists.。。yes　　Checkingif“/grub/e2fs_stage1_5”exists.。。yes　　Running“embed/grub/e2fs_stage1_5（hd0）”。。。26sectorsareembedded.　　succeeded　　Running“install/grub/stage1（hd0）（hd0）1+26p（hd0，0）/grub/stage2/grub/grub.conf”。。。succeeded　　Done.　　grub》quit//Exit

3. Restart reboot to start the system and enter the grub interface for testing.

4. find/grub/stage1 and find the/boot partition (hd0, 0). Specify kernel, initrd, and boot to start the system successfully.

5. After the system is started successfully, enter the system to re-write the/boot/grub. conf file.

6. [root @ localhost/] # vi/boot/grub. conf configuration file is as follows:

Finally, enter the content of the grub. conf file.

Default = 0 // The default menu is the first

Timeout = 6 // The wait time is 6 seconds.

Title mylinux // boot title: mylinux

Root (hd0, 0) // The partition where boot is located is/dev/sda1

Kernel/vmlinuz-2.6.32-71.el6.i686 ro root =/dev/sda3 rhgb quiet // the location of the kernel mounted in read-only mode/dev/sda3 root partition rhgb quiet for quiet mode does not display kernel information.

Initrd/initramfs-2.6.32-71.el6.i686.img // load the initrd image.

7. Go to linux rescue and create a grub.

8. The final startup interface is as follows:

The above describes how to restore the deleted boot partition in CentOS 6. The steps are long. If you are in trouble, you can reinstall the system and restore the boot partition.