LFCSStorageSingle Linux VMMedium

Swap file, tmpfs and a device under I/O load

Scenario lfcs-sto-003 · about 6 minutes · 8 points · 7 grader checks

Add a persistent swap file and a size-limited tmpfs, then find the block device under constant write load and stop the service causing it.

swap
tmpfs
fstab
iostat
performance

What you will practise

Create, enable and persist a swap file
Mount a tmpfs with size and mode options persistently
Find a busy block device and the process behind it

Start this lab

With the CLI installed and signed in, this command provisions a fresh Ubuntu 24.04 LTS virtual machine on your Mac, applies the scenario setup and prints the task below.

goldenkube start lfcs-sto-003

Task

The task text exactly as the CLI shows it. Solve it on the machine, then run goldenkube submit.

1. Create a 512 MiB swap file /var/swap/lab.swap, owned by root and readable and writable only by root. Activate it now and at every boot. 2. Mount a tmpfs at /srv/scratch with a size limit of 128 MiB and mode 1777, now and at every boot. 3. One block device on this host is under constant write load. Write its kernel name (for example sda) to /root/busy-device.txt, then find the systemd service generating the load and stop and disable it.

Requirements and details

Certification: LFCS · Linux Foundation Certified System Administrator
Domain: Storage
Difficulty: Medium
Environment: Single Linux VM
Recommended time: 6 minutes
Points: 8
Grader checks: 7
Operating system: Ubuntu 24.04 LTS
Minimum CLI version: 0.1.0
Scenario version: 1
Published: 30 Oct 2026

Grading runs locally: 7 state checks read your machine when you submit; the scenario passes when every check passes. Hints, the reference solution and the check definitions are available only inside the CLI, not on this page.

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