Ubuntu Boot problem record

Objective

Recently encountered two problems: 1. After reloading windows, Ubuntu is gone. 2. I also installed the CentOS system, I want to set boot, make CentOS as the default boot system.

So I looked up the information and recorded it.

This article is in sync with the Ubuntu boot problem record, and if you want to access the latest article, visit here

Into the unseen Ubuntu

Under Windows, you can install a EASYBCD and add Ubuntu.

To add the first need to select a bootstrapper, the default is the first on it, for insurance, the second also added.

System Select Ubuntu can

Partition Select the partition you are in, you are not sure, each one is added, boot a try.

Select Default Boot System

General-guided systems are inside/boot/grub/menu.lst or/boot/grub/grub.cfg.

The Set default = "0" or "Default 0" can be seen on line 13 (search is not found).

This number is the default guide to that. You can modify the system that you want to start by default.

Update boot list

After the general installation of Windows, Linux boot will not be displayed, so you can not go to Linux.

After we install a software under Windows, we can go into Linux, we need to update the boot list after entering.

You can update with the command below.

sudo grub-install/dev/sda

sudo update-grub