Log analysis and repair of system faults in Linux

steps :

1 viewing and analyzing /var/log/messsages log Files

2 viewing and analyzing user login logs

L AST: command is used to query user records that successfully log on to the system

L The ASTB command is used to query user records for logon failures

MBR Sector Failure

1. backing up MBR sector data

the first hard drive (SDA) of the MBR sector Backup to page 2 Fast drive. SDB 1 in the partition ( Mount Road /opt/

directory )

"fault emulation" reads the bytes of data from the device file Zerozhoong , overwriting it to the 1 Fast Drive (SDA,) thereby destroying data in the MBR sector

Restart the system , you will receive a "operating system not found" prompt message , Unable to start the host because an available operating system could not be found

recover from a flush backup file MBR Sector Data

Use REHL5 installation CD Boot , when the installation Wizard "boot" prompt , enter "Linux rescue" and enter , will be guided to the CD in the First Aid mode Linux Systems

Default language--------->continue------> Warning whether to initialize disk "No"

" OK " after confirmation, enter the " sh-3.2# " Prompt for the Bash Shell Environment

mount a hard disk partition that holds backup files (SDB1), restore data to hard disk "/dev/sda"

executes after a recovery operation has completed " Exit " command to exit the temporary shell Environment , the system will restart automatically.

After rebooting, you can see that the system is working properly. ~~~~end~~~~~

Log analysis and repair of system faults in Linux