[2024-04-28 Sun]

While fstab will not completely automate the mounting process it simplifies it by only requiring specifying the device and all option will be taken from the /etc/fstab file.

The /etc/fstab is formatted in the following way:

# <file system> <mount point> <type> <options> <dump>  <pass>

Read on to find out how to configure each part.

Use blkid to find the UUID or LABEL and TYPE of a mountable device

sudo blkid

If you do not know which output belongs to the usb you want to add to the fstab file then remove the usb again run sudo blkid again and see which line disappeared, this will be you usb. Now read of the UUID or LABEL and the TYPE.

Other ways to find the TYPE are df -T, if the usb has been mounted, or lsblk -f.

This is the place where you wish to mount the usb, it can be anywhere but /mnt/<some-directory> is often used.

Multiple options can be seperated with a ,, comma, no spaces. More options can be found in the man pages of fstab and mount.

• ro or rw: read only or read and write permissions for files on the device. One of the two must be in the options list.
• relatime: avoiding a lot of unnecessary writes.
• exec: allow executables on the device.
• nofail: fail gracefully if the device is not connected on boot.
• user: device is mountable with mount by a normal user, no sudo required.
• uid=<uid>: all files and directories are owned by the user with uid <uid>.

You can be more specific with file permission with the options fmask=<fmask>, the mask for files, and dmask=<dmask>, the mask for directories. I won't go into detail how these work but go values could be:

• fmask=113: read write permission for owner and group, and read permission for others.
• dmask=002: read, write, execute permission for owner and group and read, executed permission for others.

Determines which filesystems need to be dumped. Defaults to zero (don’t dump) if not present. For usb's zero is fine.

Pass determines the order in which filesystem checks are done at boot time. It can have three values, if it is not specified it defaults to 0.

• 0: do not check the filesystem
• 1: for root filesystem only
• 2: for other filesystems

Usb entries in /etc/fstab could look like:

# <file system>     <mount point>   <type>   <options>                               <dump>  <pass>
UUID=79b0f26c-2d0d  /mnt/usb1        ext4    rw,relatime,exec,nofail,user,uid=1000   0       2
LABEL=MY_LABEL      /mnt/usb2        ext4    rw,relatime,exec,nofail,user,uid=1000   0       2

• https://thequantitative.medium.com/auto-mount-drives-in-linux-by-configuring-etc-fstab-931b0df4a50a
• https://www.man7.org/linux/man-pages/man8/mount.8.html#FILESYSTEM-INDEPENDENT_MOUNT_OPTIONS
• man mount
• man fstab