In this short article I will tell you how the hard disks and partitions are represented, in Unix and Linux Systems:
The hard disks are represented with letters and the partitions with numbers, as I have explained in my examples.
Note: The Hard Disk representation stars from ‘a’ and the partition representation start from ‘1’.
The IDE (or ATA or PATA) Hard Disks are represented by /dev/hd?* .
Examples for representing IDE hard disks:
- First IDE Hard Disk: /dev/hda
- Second IDE Hard Disk: /dev/hdb
- Third IDE Hard Disk: /dev/hdc
Examples for representing partitions on IDE hard disks:
- First Partition on the first IDE Hard Disk: /dev/hda1
- Second Partition on the first IDE Hard Disk: /dev/hda2
- Third Partition on the first IDE hard Disk: /dev/hda3
The SCSI and S-ATA Hard Disks are represented by /dev/sd?*
Examples for representing SCSI and S-ATA hard disks:
- First S-ATA and SCSI Hard Disk: /dev/sda
- Second S-ATA and SCSI Hard Disk: /dev/sdb
- Third S-ATA and SCSI Hard Disk: /dev/sdc
Examples for representing partitions on S-ATA or SCSI hard disks:
- First Partition on the first S-ATA and SCSI Hard Disk: /dev/sda1
- Second Partition on the first S-ATA and SCSI Hard Disk: /dev/sda2
- Third Partition on the first S-ATA and SCSI hard Disk: /dev/sda3
The Grub has different notations for the hard disks and partitions.
The first SCSI CDROM is representated by /dev/sr0, the first SCSI joystick is /dev/js0 and the first floppy drive by /dev/fd0.