7. /etc/fstab
Lesson Content
When we want to automatically mount filesystems at startup we can add them to a file called /etc/fstab (pronounced “eff es tab” not “eff stab”) short for filesystem table. This file contains a permanent list of filesystems that are mounted.
pete@icebox:~$ cat /etc/fstab
UUID=130b882f-7d79-436d-a096-1e594c92bb76 / ext4 relatime,errors=remount-ro 0 1
UUID=78d203a0-7c18-49bd-9e07-54f44cdb5726 /home xfs relatime 0 2
UUID=22c3d34b-467e-467c-b44d-f03803c2c526 none swap sw 0 0
Each line represents one filesystem, the fields are:
- UUID - Device identifier
- Mount point - Directory the filesystem is mounted to
- Filesystem type
- Options - other mount options, see manpage for more details
- Dump - used by the dump utility to decide when to make a backup, you should just default to 0
- Pass - Used by fsck to decide what order filesystems should be checked, if the value is 0, it will not be checked
To add an entry, just directly modify the /etc/fstab file using the entry syntax above. Be careful when modifying this file, you could potentially make your life a little harder if you mess up.
Exercise
Add the USB drive we’ve been working on as an entry in /etc/fstab, when you reboot you should still see it mounted.
Quiz Question
# What file is used to define how filesystems should be mounted?
> The /etc/filesystems file is used to define mounts to be automatic at system initialization. The mount command is used to mount after system startup.
1. [ ] /root
2. [ ] /mount
3. [ ] /dev
4. [x] /etc/fstab