Linux boot error MBR

When starting the Linux operating system, sometimes due to misuse of the system will not start normally, and these errors are related to grub, here we have a simple simulation of this situation and solve the problem of not starting properly. First, let's take a look at the Linux startup flowchart:

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Simulation of the first phase failure and repair
We use a command to simulate the first 446 bytes of the MBR by overriding the method.

Then we restart the Linux system, this time only this interface, and can't get into the system

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Next we will find a way to get the system back to normal, first we have to add the CD-ROM drive, and then reboot, to boot on the CD. An interface like this will appear:

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Then we have to go into rescue mode to repair the system. Enter the rescue mode by entering a command at the back of the boot:
The interface that Linux rescue will enter at this time

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Then press ENTER to continue, when the interface appears

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Since we are trying to simulate the repair system, configure the network here to select No and continue until it appears

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At this point we are going to switch to this directory and use the Chroot/mnt/sysimage command. Then we can execute the order.
Because this is the first stage of the problem, so we have to install the first phase of the required files,
Using the command: GRUB-INSTALL/DEV/SDA

Then the installation is ready, we will restart the system, then the system will return to normal.

This article is from the "Jeffery blog" blog, please be sure to keep this source http://oceanszf.blog.51cto.com/6268931/1531805