How to mount disks and partitions in Linux

Mounting disks and partitions in Linux attaches additional storage devices to the active filesystem so applications and users access data through regular directories instead of raw devices. Consistent mounts keep extra system, data, and backup volumes reachable in predictable locations, whether backed by virtual disks, internal drives, or removable media.

The Linux storage stack exposes each disk as a block device such as /dev/sda and partitions such as /dev/sda1. The mount command binds a filesystem from such a device to a mount point directory, while tools like lsblk and blkid enumerate devices, report filesystem types, and show UUID values that provide more stable identifiers than raw device names.

Most mounting operations require elevated privileges because incorrect options or entries in /etc/fstab can prevent services from starting correctly or even block boot. Choosing a suitable mount point, deciding whether the mount is temporary or persistent, and validating configuration changes with mount -a before rebooting reduces the risk of losing access to stored data.

1. Open a terminal with a user account that has sudo privileges.
2. Identify the disk or partition that requires mounting by listing block devices.

   $ lsblk
   NAME                      MAJ:MIN RM  SIZE RO TYPE MOUNTPOINTS
   loop0                       7:0    0    1G  0 loop 
   ├─loop0p1                 259:3    0  256M  0 part /root/disk
   ├─loop0p2                 259:4    0  128M  0 part /mnt/uuidtest
   └─loop0p3                 259:5    0  256M  0 part /mnt/uuiddemo
   loop1                       7:1    0  300M  0 loop 
   sda                         8:0    0   64G  0 disk 
   ├─sda1                      8:1    0    1G  0 part /boot/efi
   ├─sda2                      8:2    0    2G  0 part /boot
   └─sda3                      8:3    0 60.9G  0 part 
     └─ubuntu--vg-ubuntu--lv 252:0    0 30.5G  0 lvm  /
   sr0                        11:0    1 1024M  0 rom  
   ##### snipped #####

3. Determine the filesystem type and UUID of the target partition.

   $ sudo blkid /dev/loop0p1
   /dev/loop0p1: LABEL="data" UUID="ed6aa5ab-3a4d-43bd-b7d2-ffec8c1d0291" BLOCK_SIZE="4096" TYPE="ext4" PARTLABEL="primary" PARTUUID="7394612e-0563-40a3-bcae-6c2b5a55ff3d"

4. Create a directory under the home directory to act as the mount point if it does not already exist.

   $ sudo mkdir -p /root/disk

5. Temporarily mount the disk or partition to the mount point to test access.

   $ sudo mount -t ext4 /dev/loop0p1 /root/disk

   Replace ext4 with the filesystem type reported by blkid when mounting non-ext4 filesystems.

6. Verify that the disk or partition is mounted at the expected path.

   $ sudo df -h
   Filesystem                         Size  Used Avail Use% Mounted on
   tmpfs                              391M  1.3M  389M   1% /run
   efivarfs                           104K  4.9K  100K   5% /sys/firmware/efi/efivars
   /dev/mapper/ubuntu--vg-ubuntu--lv   30G  6.1G   23G  22% /
   tmpfs                              2.0G     0  2.0G   0% /dev/shm
   tmpfs                              5.0M     0  5.0M   0% /run/lock
   /dev/sda2                          2.0G  195M  1.6G  11% /boot
   /dev/sda1                          1.1G  6.4M  1.1G   1% /boot/efi
   ##### snipped #####
   /dev/loop0p1                       224M   24K  206M   1% /root/disk
   /dev/loop0p2                       104M   24K   95M   1% /mnt/uuidtest
   /dev/loop0p3                       224M   24K  206M   1% /mnt/uuiddemo

7. Unmount the previously mounted partition after testing access.

   $ sudo umount /dev/loop0p1

8. To mount the disk automatically at startup, edit the /etc/fstab file with elevated privileges.

   $ sudo vi /etc/fstab

   An incorrect entry in /etc/fstab can prevent Linux from booting until the file is corrected.

9. Add an entry in /etc/fstab for the disk or partition using the chosen device identifier.

   /dev/loop0p1       /root/disk ext4    defaults        0       0

   For more robust configuration, prefer the UUID value from blkid as shown in How to mount disk partitions using UUID in Linux instead of the raw /dev path.

10. Apply the configuration by mounting all filesystems defined in /etc/fstab.

    $ sudo mount -a

11. Confirm that the disk or partition is mounted according to the /etc/fstab entry.

    $ sudo df -h
    Filesystem                         Size  Used Avail Use% Mounted on
    tmpfs                              391M  1.3M  389M   1% /run
    efivarfs                           104K  4.9K  100K   5% /sys/firmware/efi/efivars
    /dev/mapper/ubuntu--vg-ubuntu--lv   30G  6.1G   23G  22% /
    tmpfs                              2.0G     0  2.0G   0% /dev/shm
    tmpfs                              5.0M     0  5.0M   0% /run/lock
    /dev/sda2                          2.0G  195M  1.6G  11% /boot
    /dev/sda1                          1.1G  6.4M  1.1G   1% /boot/efi
    ##### snipped #####
    /dev/loop0p1                       224M   24K  206M   1% /root/disk
    /dev/loop0p2                       104M   24K   95M   1% /mnt/uuidtest
    /dev/loop0p3                       224M   24K  206M   1% /mnt/uuiddemo