Installing Grub using grub-install: in rescue installed system centos 6/Rhel/Fedora

#df -h

check the filesystem name of /boot

#cd /sbin

#grub-install /dev/sda5 /* where /dev/sda5 is /boot filesystem name*/

output:

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 of the lines is incorrect,

fix it and re-run the script `grub-install'.

# this device map was generated by anaconda

(hd0) /dev/sda

#reboot