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Auto-Mount Secondary Disks at Boot on Linux

When you have multiple disks on your computer, eg NVMe for OS and two other HDD for storing data and backup. In this setting, the drive for OS will be auto-mounted and OS will be loaded but the remaining two will remain unmounted. This gist will show how to mount a secondary disk automatically at startup using fstab in linux.

Identify the Disk and Partition​

Use lsblk to list available disks and partitions:

lsblk

Example output:

NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
loop0         7:0    0     4K  1 loop /snap/abc/5
loop1         7:1    0 183.9M  1 loop /snap/xyz/3199
sda           8:0    0   1.8T  0 disk /mnt/DATA
sdb           8:16   0   1.8T  0 disk /mnt/BACKUP
nvme0n1     259:0    0 953.9G  0 disk 
├─nvme0n1p1 259:1    0   512M  0 part /boot/efi
├─nvme0n1p2 259:2    0     6G  0 part 
├─nvme0n1p3 259:3    0   100G  0 part /
├─nvme0n1p4 259:4    0    32G  0 part [SWAP]
└─nvme0n1p5 259:5    0 815.4G  0 part /home

From the above we're going to mount both sda & sdb.

Create a Mount Point​

Create a directory where the partition will be mounted:

sudo mkdir -p /mnt/DATA

You can change /mnt/DATA to any path you prefer.

Get UUID or Label of the Partition​

UUID - Universally Unique Identifier​

Use blkid to copy the UUID or label of the drive you need to mount automatically.

Any one of these (UUID or Label) can be used in the next step.

sudo blkid

Example output:

/dev/nvme0n1p5: LABEL="HOME" UUID="e81ddf3b-39f8-508d-a6ee-0f481032ca5e" TYPE="ext4"
/dev/sda: LABEL="DATA" UUID="1969916a-c7c7-69d2-a143-2800e675a761" TYPE="ext4"
/dev/sdb: LABEL="BACKUP" UUID="1CE3751F6BE6CF0D" TYPE="ntfs"

Edit /etc/fstab to Add the Disk​

Open /etc/fstab in a text editor:

sudo nano /etc/fstab

Add the following line at the end (replace the UUID and mount point with your own):

<file system>            <mount point>   <type>   <options>   <dump>  <pass>
LABEL=DATA               /mnt/DATA       ext4     defaults    0       2
UUID="1CE3751F6BE6CF0D"  /mnt/BACKUP     ntfs     defaults    0       2

Test the Configuration​

Test the mount without rebooting:

sudo mount -a

If there are no errors, the configuration is correct.

I got an error here mount: /mnt/somemountpoint: special device LABEL=xyz does not exist., through which I found the step Get UUID or Label of the Partition

Verify the Mount​

Check that the partition is mounted properly:

df -h

Example output:

/dev/sda  1.8T  923G  818G  54%  /mnt/DATA
/dev/sdb  1.9T  1.7T  165G  92%  /mnt/BACKUP

Now your secondary disks will auto-mount on booting. So that's it!!!