I‘ve installed an usb image on Pen drive along with MBR. Now, I need to use this USB pen for other purpose. Is there a way in Linux to delete the mbr (just like dos fdisk /mbr command)?
You can delete the mbr (master boot recored) using the dd command itself. A master boot record (MBR) is the 512-byte boot sector that is the first sector of a partitioned data storage device of a hard disk.
Understanding MBR size
The mbr size is as follows in bytes:
Where,446 + 64 + 2 = 512
- 446 bytes – Bootstrap.
- 64 bytes – Partition table.
- 2 bytes – Signature.
Option #1: Command to delete mbr including all partitions
Open a terminal and type the following command command to delete everything:
# dd if=/dev/zero of=/dev/sdc bs=512 count=1
1+0 records in 1+0 records out 512 bytes (512 B) copied, 0.00308483 s, 166 kB/s
- if=/dev/zero – Read data from /dev/zero and write it to /dev/sdc.
- of=/dev/sdc – /dev/sdc is the USB drive to remove the MBR including all partitions.
- bs=512 – Read from /dev/zero and write to /dev/sdc up to 512 BYTES bytes at a time.
- count=1 – Copy only 1 BLOCK input blocks.
Option #2: Command to delete mbr only
The following command will erase mbr, but not your partitions:
# dd if=/dev/zero of=/dev/sdc bs=446 count=1
- bs=446 – Read from /dev/zero and write to /dev/sdc up to 446 BYTES bytes at a time.
- Linux: How to backup hard disk partition table (MBR)
- man pages – dd