MBR sector failure of the CentOS system startup failure

Cause of failure

Viruses, trojans, improper partitioning operations, disk read and write errors, etc.

Failure phenomena

Boot program not found, start interrupt

Unable to load operating system, black screen after boot

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Workaround-Prerequisites

The premise of this workaround is to do a backup of the MBR sector data beforehand.

The backup method is as follows ( to be backed up to another disk ):

[email protected] ~]# Mount | TAIL-1/DEV/SDB1 on/backup type EXT4 (rw) [[email protected] ~]# dd if=/dev/sdaof=/backup/sda_mbr.bak bs=512 count=1 recorded 1 + 0 reads the 1+0 write 512 bytes (+ B) copied, 0.000264295 seconds, 1.9 mb/s

-Workaround

CD-ROM boot, enter the first aid mode, follow the instructions

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-- Creating directories, mounting partitions

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-- restore MBR sector, restart

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-- Normal access to the system, repair success

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This article is from the "12241288" blog, please be sure to keep this source http://12251288.blog.51cto.com/12241288/1878467

MBR sector failure of the CentOS system startup failure