O'Reilly logo

Linux Pocket Guide, 2nd Edition by Daniel J. Barrett

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Disks and Filesystems

df

Display available space on mounted filesystems.

mount

Make a disk partition accessible.

umount

Unmount a disk partition (make it inaccessible).

fsck

Check a disk partition for errors.

sync

Flush all disk caches to disk.

Linux systems can have multiple disks or disk partitions. In casual conversation, these are variously called disks, partitions, filesystems, volumes, even directories. We’ll try to be more accurate.

A disk is a hardware device, which may be divided into partitions that act as independent storage devices. Partitions are represented on Linux systems as special files in (usually) the directory /dev. For example, /dev/sda7 could be a partition on your hard drive. Some common devices in /dev are:

hda

First IDE bus, master device; partitions are hda1, hda2, ...

hdb

First IDE bus, slave device; partitions are hdb1, hdb2, ...

hdc

Second IDE bus, master device; partitions are hdc1, hdc2, ...

hdd

Second IDE bus, slave device; partitions are hdd1, hdd2, ...

sda

First block device, such as SCSI, SATA, USB, or Firewire hard drives; partitions are sda1, sda2, ...

sdb

Second block device; partitions are sdb1, sdb2, ... Likewise for sdc, sdd, ...

ht0

First IDE tape drive (then ht1, ht2, ...) with auto-rewind

nht0

First IDE tape drive (then nht1, nht2, ...) without auto-rewind

st0

First SCSI tape drive (then st1, st2, ...)

scd0

First SCSI CD-ROM drive (then scd1, scd2, ...)

fd0

First floppy drive (then ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required