Mounting in Linux: mount, fstab and lsblk

mount attaches a partition's filesystem to a directory in the single tree, and umount detaches it.

Syntax

sudo mount device directory

Common cases

lsblk                        # disks and partitions as a tree
sudo mount /dev/sdb1 /mnt     # attach a partition at /mnt
df -h /mnt                   # check that it mounted
sudo umount /mnt             # detach it
blkid                        # the UUID and type of filesystems
cat /etc/fstab               # what mounts at boot

How it works: one tree, mount points

Linux has no drive letters like Windows. Any disk or partition is attached (mounted) to some directory - a mount point, and its contents appear inside the single tree from /. Running mount with no arguments shows everything already mounted. To mount a partition automatically at every boot, you list it in /etc/fstab. There it is best to name the disk by its UUID (from blkid), because names like /dev/sdb1 can swap around between reboots.

In the book

This topic is covered in full in the chapter Disks, filesystems, and inodes.

See also

df and du, Free inodes: df -i, What an inode is, LVM: logical volumes.