You need the UUID of the filesystem on /dev/sda1 to write a persistent /etc/fstab entry. Select the TWO commands that will show it.
LPIC-1 Exam 101-500, objective 104. Devices, Linux filesystems, filesystem hierarchy standard medium
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How these questions are written — where each question comes from, what the verification ledger records, and what happens when one is found wrong.
The options
Choose 2.
Not correct df -h /dev/sda1
Wrong. df reports size, used and available space plus the mount point of a mounted filesystem. It never prints a UUID.
Correct blkid /dev/sda1
Correct. blkid reads the filesystem signature on a block device and prints its UUID, LABEL and TYPE. With no argument it lists every device it can identify.
Not correct du -sh /dev/sda1
Wrong. du sums the disk usage of files; given a device node it just reports the size of that node's directory entry, which is meaningless here.
Correct lsblk -f
Correct. -f adds filesystem type, label, UUID and mount point to lsblk's tree of block devices, which is the fastest way to see the whole picture at once.
Not correct mount -a
Wrong. mount -a mounts every eligible entry in /etc/fstab. It performs an action and prints no identification data.
Why
blkid and `lsblk -f` are the two everyday ways to read filesystem UUIDs and labels. udev also maintains symlinks under /dev/disk/by-uuid/ and /dev/disk/by-label/, so `ls -l /dev/disk/by-uuid` shows the same mapping. For ext filesystems tune2fs -l and dumpe2fs -h report the UUID too.
Where this comes from
- Cited
- LPI exam objective 104.3
- What it says
- Use blkid and lsblk to identify filesystems by UUID and label.
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 104 and space the ones you get wrong.
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