MARICOPA COUNTY, Ariz., Oct. 18, 2026 — Coffey Labs today brought back the LINUXexpert study guides, on a site of their own at linuxexpert.net. The guides went offline when LINUXexpert.org retired in August. Since then, enough people have asked for them that they are back, refreshed and in a new format.
Ten guides are live: LFCA, LFCS, KCNA, KCSA, CKA, CKAD, CKS, PCA, OTCA and LPIC-1. Each one is written from the exam’s published objectives and opens with an overview of the exam: its domains and their weights, the cost, the time allowed, and how the guide gets the reader ready. Every chapter explains its topic, points out what the exam looks for, gives the reader something to try on a real system, and ends with a short quiz. Guides for the Istio Certified Associate and Cloud Native Platform Engineer exams are in the works.
“More people were using the old LINUXexpert study guides than I thought,” said John Coffey, founder of Coffey Labs. “I’ve had a lot of requests to bring them back, so I have.”
Why an account. The first chapter of every guide is open to anyone, no login needed. The rest of each guide needs an account, which costs nothing. It is there to keep AI crawlers from scraping the whole library.
What comes next. Practice exams are coming soon. Further out are a brag board, where people can share it when they sit and pass an exam, badges, and perhaps a community area.
LINUXexpert.org stays on Mastodon. The original domain keeps the job it took on in September, as a Mastodon server for the Linux community. The study guides live at linuxexpert.net.
About Coffey Labs
Coffey Labs LLC is an Arizona company that builds, owns and maintains open-source infrastructure software: the inbuxa mail suite, ihasmail webmail, the ihasvpn WireGuard server, Cairn OBS log aggregation and the HotDog CMS website builder, plus the tools around them. Everything it makes runs on the user’s own hardware, is published in full under a copyleft license, and has no paid tier. Coffey Labs started in 2018 as LINUXexpert.org and was organized as an LLC in 2026. Learn more at coffeylabs.org.