How to reinstall grub in Centos

If centos is installed first and then win is installed in the dual-system, there will be no problems at startup. However, if the order is reversed or the dual-system is completed and win is re-installed, the MBR will be overwritten, in this way, GRUB or LILO will disappear, or GRUB will disappear for some reason. In this case, you only need to reinstall GRUB and do not need to re-run the linux system.

There are many methods to reinstall GRUB. Here we record a method for successfully installing GRUB on my computer. My system is fedora14:

Start with the installation disc (or the system's USB flash drive). After Entering the installation interface, select rescue mode (seeking mode) and click OK until the # command prompt appears, enter the following commands in sequence,

1. chroot/mnt/sysimage

2. grub-install/dev/sda --- whether the input sda or hda is related to the hard disk type. If all the partitions are sda1, sda2 ......, The hard disk type is sda, or hda.

If a prompt such as "install finished" "no error" is displayed, the installation is successful. restart the computer and enter the grub System Selection interface.