Centos 7 recover grub

I use an old computer for testing purposes at home, one problem of grub is when you install a windows system it removes grub and you can’t access to your Centos 7 system.

reinstall grub is really easy.

step 1.

Boot your computer from a dvd o flash memory with centos 7 install disk

step 2.

select troubleshooting menu

Centos 7 boot troubleshootingstep 3

Select rescue a Centos system

centos 7 rescue a centos systemStep 4

when boot ask you how to mount a system select continue and it gives you access to a shell.

Centos 7 grub recoverwrite

grub2-install –root-directory=/mnt/sysimage/ /dev/sda

a then reboot