Grub recovery in centos 7 , redhat 7

Grub recovery in centos 7 , redhat  7

In this session, we will try to corrupt the kernel file,

In this we corrupt the grub menu by using dd command

After deleting kernel file ,

Reboot the system

After reboot it will show you like this

You can recover kernel by using bootable centos cd / pendrive [ because we are booting centos file ]

So after using bootable pendrive.

Click on CD-ROM drive or removable devices depend upon you bootable device.

After clicking on troubleshooting,

Click on rescue a centos Linux system,

After click the rescue mode it will go through some process and take some times.

It will ask for selection

Press 1 and enter

And it will ask again for enter

Press enter to get into rescue mode.

After pressing 1 and you need to press enter to get into shell

After pressing enter,

Now we need to use command to get into prompt of system [ bash ]

Use this command to get into bash shell of system [ main ]

#chroot /mnt/sysimage

You will see after using chroot command we get into our main system.

Now we need to install the kernel file.

Now we need to update using grub command

After installing check the boot file

It will directly go through the grub menu of system which u deleted.