Retrieve Grub2 covered by Windows 8 boot (BOOT Ubuntu)

Retrieve Grub2 (BOOT Ubuntu) that is covered by Windows 8 boot. After installing win8, grub will be overwritten. It is useless to try many methods, the Grub command line on the PE disc I used cannot recognize the files in the Linux partition, and the display is garbled. I had to build a Grub2 boot USB flash drive myself. Www.2cto.com first you need a Linux system to install Grub2 on a USB flash drive. I got Ubuntu12.04 on the virtual machine, because there is an image on hand. First, make sure that your USB flash drive can be started from MBR. If you are not sure that you can format it again in Linux, select the MBR mode. I use the built-in formatting tool Ubuntu. Before formatting, cancel the mounting. Create a partition after the format is complete. Run sudo grub-install -- boot-directory =/media/u -- recheck/dev/sdb u to specify the name of the mounted folder and sdb to specify the device name. Www.2cto.com. Then restart the computer and start from the USB flash drive. The Grub command line is displayed. Grub2 and Grub commands are different. You can check them and I won't talk about them anymore. According to the information found on the internet, I loaded the kernel with linux after set root, loaded the memory disk with initrd, and then boot .... Unfortunately, it should be Linux in the memory disk, not Ubuntu on the disk. I don't know why. The online materials may be old and can only be used by yourself. Go through the Grub2 manual and find the normal [FILE] command to load the Grub2 menu. This is easy, as long as the original boot menu is loaded, it should be able to guide correctly. Set root = (hd0, 4) normal/boot/grub. cfg and then the Grub boot menu is ready.