What does the CompTIA Linux+ (XK0-006) path on CertGrid cover?

28 hands-on guides across 8 tracks, about 661 minutes of reading in total. Vendor-neutral administration, automation and troubleshooting. Each guide is a walkthrough with real commands and real output rather than a summary.

Are these hands-on labs or written guides?

Written guides built around commands you run yourself. Every step shows the command and the output you should see, so you can follow along on your own machine or cluster and check each result as you go. CertGrid does not host a live terminal or a managed cluster - you bring the environment, and the guide tells you exactly what to do in it.

Do I need my own environment to follow along?

Yes, and that is deliberate. The guides are written against real systems, and the value is in running the commands rather than reading them. Most guides say up front what they assume you have - a Linux host, a cluster, a database - and several start by setting that up.

Can I read any of the CompTIA Linux+ (XK0-006) guides for free?

Yes. 8 of the 28 guides are free to read with no account and no payment, and the remaining 20 need path access.

Does buying a CertGrid practice exam unlock these guides?

Yes. Path access to these guides is included when you own the matching CertGrid practice exam, and it is also sold on its own if you only want the guides.

How much does access to the CompTIA Linux+ (XK0-006) path cost?

One-time access is $7.99. That covers all 20 paid guides in this path, including any added to it later.

CompTIA Linux+ Guides, Labs and Troubleshooting

Start Here3 guides

What XK0-006 asks, how it is scored, and the lab it is sat against.

Concepts 11 min

Linux+ XK0-006 domains and question style

Five domains, 90 questions, 90 minutes - and the scoring scale that makes "how many can I get wrong" unanswerable.

All five domains

Updated 25 Aug 2026
Hands-on Lab 14 min

Linux+ lab: Ubuntu and AlmaLinux package families

Two machines, because the exam will not tell you which family you are getting.

All five domains

Updated 25 Aug 2026
Concepts 13 min

How Linux+ differs from LFCS and RHCSA

Two things this exam has that neither of the others does - and they are on the machine, not in a syllabus.

All five domains

Updated 25 Aug 2026

System Management5 guides

Filesystems, storage, processes, packages and the boot path. 23%.

Hands-on Lab 26 min

A disk, a filesystem, and a mount that survives a reboot

Storage from an empty file to a fstab line, on both families, with the check that stops a bad line stranding the machine.

Domain 1 - System Management

Updated 30 Aug 2026
Hands-on Lab 24 min

Processes, boot, and what systemd started

Where the boot time went, what a target really is, and which signals a process is allowed to refuse.

Domain 1 - System Management

Updated 30 Aug 2026
Hands-on Lab 24 min

Packages, repositories, and proving nothing changed

Install, query and remove on both families - and the one command that proves a file on disk still matches the package that shipped it.

Domain 1 - System Management

Updated 31 Aug 2026
Hands-on Lab 26 min

LVM, from physical volume to a filesystem that grows

Three layers built in order, a volume that grows while mounted, and the second command most people forget.

Domain 1 - System Management

Updated 31 Aug 2026
Hands-on Lab 22 min

Swap: a file, a partition, and how eagerly it is used

Two swap areas added on a running machine, the priority that decides which is used, and the one number people change without knowing what it means.

Domain 1 - System Management

Updated 31 Aug 2026

Services and Users5 guides

systemd services, accounts, permissions and network services. 20%.

Hands-on Lab 24 min Paid

A service, an account, and the permission between them

A unit that runs as its own user, broken on a directory it cannot write, and fixed at the layer that was actually wrong.

Domain 2 - Services and User Management

Updated 30 Aug 2026
Hands-on Lab 24 min Paid

Accounts, sudo, and what a login reads

Where a new account's defaults come from, a sudo rule validated before it is trusted, and the one flag that decides which startup files run.

Domain 2 - Services and User Management

Updated 30 Aug 2026
Hands-on Lab 24 min Paid

Network configuration on both families

Where an address actually comes from on each family, and the difference between a change that survives a reboot and one that does not.

Domain 2 - Services and User Management

Updated 31 Aug 2026
Hands-on Lab 26 min Paid

The SSH server and what blocks a login

Why a correct key is still refused, and how the exit code tells you whether the server rejected you or the shell did.

Domain 2 - Services and User Management

Updated 31 Aug 2026
Hands-on Lab 28 min Paid

Publishing a service and the three ways a client fails

Why a running service with an open port is still unreachable, and the one command on the server that tells the three causes apart.

Domain 2 - Services and User Management

Updated 31 Aug 2026

Security5 guides

Hardening, SELinux and AppArmor, firewalls, keys and certificates. 18%.

Hands-on Lab 28 min Paid

SELinux and AppArmor, side by side

The same refusal on both families - one keyed to a label, one to a path - and the experiment that identifies it when nothing is logged.

Domain 3 - Security

Updated 30 Aug 2026
Hands-on Lab 24 min Paid

Keys, certificates, and what the server allows

A key pair from both ends, the permission the client refuses to ignore, and a certificate that proves nothing until you say who signed it.

Domain 3 - Security

Updated 30 Aug 2026
Hands-on Lab 24 min Paid

The firewall on both families, and what survives a reload

Two front ends over one kernel, a rule that does nothing until the firewall is on, and one that vanishes at the next reload.

Domain 3 - Security

Updated 31 Aug 2026
Hands-on Lab 26 min Paid

ACLs and what new files inherit

Access for a user the mode bits cannot express, why chmod appears to lie once an ACL exists, and what a new file in the directory gets.

Domain 3 - Security

Updated 31 Aug 2026
Hands-on Lab 28 min Paid

Password policy and account expiry

Why editing the policy file changes nothing for existing users, and which control actually stops an account that has a working key.

Domain 3 - Security

Updated 31 Aug 2026

Troubleshooting5 guides

Storage, network, CPU, memory and permission faults, diagnosed. 22%.

Troubleshooting 24 min Paid

Faults, and the order that finds them

Three commands that rule out three domains, then one diagnostic per fault - including the full disk that df and du disagree about.

Domain 5 - Troubleshooting

Updated 30 Aug 2026
Troubleshooting 26 min Paid

Memory, permissions, and what the machine complains about

A memory limit that swaps instead of killing, a 644 file nobody can read, and the two commands that triage a machine you have just been handed.

Domain 5 - Troubleshooting

Updated 30 Aug 2026
Hands-on Lab 26 min Paid

Storage faults: full, out of inodes, and busy

Two different faults that both say No space left on device, and a third that makes a filesystem impossible to unmount.

Domain 5 - Troubleshooting

Updated 31 Aug 2026
Hands-on Lab 27 min Paid

Network faults, from the client outwards

The order to check things in when nothing connects, and proof that a failing ping tells you almost nothing.

Domain 5 - Troubleshooting

Updated 31 Aug 2026
Hands-on Lab 28 min Paid

A service that will not start

Four reasons a unit refuses, the exit code that names each one, and why systemctl start exiting 0 proves nothing at all.

Domain 5 - Troubleshooting

Updated 31 Aug 2026

Automation and Scripting4 guides

Shell scripting, git, containers and infrastructure as code. 17%.

Hands-on Lab 26 min Paid

Bash, Git, and rootless containers in one workflow

The same script twice - once that lies about succeeding and once that does not - then under git, then running rootless.

Domain 4 - Automation, Orchestration, and Scripting

Updated 30 Aug 2026
Hands-on Lab 24 min Paid

A Containerfile, an image, and what it runs as

Eight instructions, four layers, and the difference between ENTRYPOINT and CMD shown by running the same image twice.

Domain 4 - Automation, Orchestration, and Scripting

Updated 30 Aug 2026
Hands-on Lab 26 min Paid

cron, timers, and one-off jobs

One job written twice, both left to fire, and the environment that explains why scheduled work fails when yours does not.

Domain 4 - Automation, Orchestration, and Scripting

Updated 31 Aug 2026
Hands-on Lab 24 min Paid

Infrastructure as code, idempotence and drift

The four words the objective lists, made concrete by one playbook run four times - including once that changes nothing on purpose.

Domain 4 - Automation, Orchestration, and Scripting

Updated 31 Aug 2026

Readiness1 guide

The 90-question format, the 720/900 scale, and what PBQs reward.

Concepts 14 min Paid

Ninety questions, and where the marks are

Two pools ship and only one is this exam - then the weights, the clock, and the keyword counts that decide what to revise.

All five domains

Updated 30 Aug 2026

Command Cheat Sheets1 sheet

Searchable references across all five domains.

Reference 12 min

Linux+ XK0-006 command cheat sheet

Every command this path proves, grouped the way the exam weights them.

findmnt --verify · namei -l · lsof +L1 · podman history

Updated 31 Aug 2026