Drive Naming Schemes in Linux
If you've used linux before, you'll probably have seen your flash drive or hard drive appearing as
/dev/sdc4 at one point or another. You may have a cd drive which appeared as
/dev/cdrom. If you're really lucky, you might even have a tape drive that appears as
What do all of these letters mean? I was wondering the same thing, so I looked it up and am writing up what I found in this post.
It would appear that in linux devices have a prefix and then an identifier. Before I explain the identifiers, I should outline each of the prefixes that I've come across (or looked up) first. You can find them below.
By far the most common device name prefix that I have come across is
sd. This apparently originally stood for SCSI (SATA?) Device, but today it represents any regular block device that can be used for storage. This includes hard drives and flash drives for example.
hd prefix originally stood for Hard Disk and was used for IDE drives, but it was dropped as of Linux 2.6.19 and
sd* is now used instead.
sr stands for SCSI ROM and is used for CD / DVD drives (It might be used for blu-rays too, but I don't have one to check. Please post in the comments if you do!). On my machine, I have a number of symbolic links leading back to this drive in my
I have not come across a device with this prefix yet. If you have one, please post in the comments below! It stands for SCSI Tape drive.
The numbers and / or letters after the prefix refer to the device number, and, if appropriate, partition on the device. For example,
/dev/sdb4 refers to the 4th partition on the 2nd disk,
/dev/sr2 refers to the 3rd CD / DVD drive, and
/dev/hdc3 refers to the 3rd partition on the 3rd IDE hard drive.
- Super User - What does /dev/sda for linux mean?
- Ask Ubuntu - What is the Linux drive naming scheme?
- The Linux Documentation Project - Drive Naming in Linux