Repair and Manage Bad Blocks Using the mbadblocks Command
In this step, you will learn how to repair and manage bad blocks on a Linux file system using the mbadblocks
command.
First, let's create another test file to simulate the presence of bad blocks:
cd ~/project
dd if=/dev/zero of=testfile2.txt bs=1M count=100
Now, let's use the mbadblocks
command to scan the file system and identify any bad blocks:
sudo mbadblocks /dev/sda1
Example output:
Checking blocks 0 to 20971519...
Marking bad block 12345 as unusable
Marking bad block 67890 as unusable
In this example, the mbadblocks
command has identified two bad blocks at block numbers 12345 and 67890.
To repair the file system and relocate data from the bad blocks, you can use the -r
(repair) option:
sudo mbadblocks -r /dev/sda1
Example output:
Checking blocks 0 to 20971519...
Relocating data from bad block 12345 to spare block 54321
Relocating data from bad block 67890 to spare block 98765
The mbadblocks
command has relocated the data from the bad blocks to spare blocks, effectively repairing the file system.
You can also use the mbadblocks
command to mark specific blocks as bad, which can be useful if you know that certain blocks are problematic:
sudo mbadblocks -m 54321 /dev/sda1
This will mark the block at number 54321 as a bad block, preventing data from being written to it.
Additionally, you can use the mbadblocks
command to list the current bad blocks on the file system:
sudo mbadblocks -l /dev/sda1
Example output:
Bad blocks on /dev/sda1:
12345
67890
By using the mbadblocks
command, you can effectively identify, repair, and manage bad blocks on your Linux file system, ensuring the integrity and reliability of your data.