Quickly locate the UUIDs that tie disks to mounts and make system boots predictable. 16.11.2025 | reading time: 2 min UUIDs keep mounts stable across reboots; an admin needs to know where to look and how to verify them quickly with a few commands like `blkid` and `lsblk`. Hands-on example Run these commands on a test VM and read the UUIDs from the output; the following shows `lsblk`, `blkid` and the udev symlink view: ```bash $ lsblk -f NAME FSTYPE LABEL UUID MOUNTPOINT sda └─sda1 ext4 3b9a1c2d-4e5f-6a7b-8c9d-0e1f2a3b4c5d / $ blkid /dev/sda1 /dev/sda1: UUID="3b9a1c2d-4e5f-6a7b-8c9d-0e1f2a3b4c5d" TYPE="ext4" PARTUUID="0001" $ ls -l /dev/disk/by-uuid/ total 0 lrwxrwxrwx 1 root root 10 Aug 10 12:00 3b9a1c2d-4e5f-6a7b-8c9d-0e1f2a3b4c5d -> ../../sda1 ``` Deeper options Use UUIDs in `/etc/fstab` as `UUID=...` for stable mounts, prefer PARTUUID for raw partition-table references in some boot scenarios, and extract single values with `blkid -o value -s UUID /dev/sda1`; for ext filesystems `tune2fs -l /dev/sda1` reveals the same UUID, while `cryptsetup luksUUID /dev/sda2` shows a LUKS container UUID — change a UUID only with care because it will break fstab and boot scripts. Related utilities udev creates the `/dev/disk/by-uuid` links so `udevadm` can help inspect device properties, `findfs` locates a filesystem by UUID for scripts, and `lsblk -f` offers a compact overview combining device, type and UUID; combine these tools when automating mount or recovery tasks. Final note UUIDs are small but critical anchors for a reliable Linux system; learn to inspect and use them confidently and keep recovery steps ready, and if he wants a deeper, exam-focused study path he should consider preparing for CompTIA Linux+ or LPIC-1 with intensive courses like bitsandbytes.academy. Join Bits & Bytes Academy First class LINUX exam preparation. filesystem utilities storage boot-process troubleshooting
