Challenge ·Medium

Broken Man Pages: whatis Returns Nothing Appropriate

Mister P
by  Mister P · on
Linux
The man page database on this system is broken — whatis and apropos return "nothing appropriate" for every query. Diagnose the root cause and restore full functionality of the shell help tools.
#man-pages#whatis#apropos#mandb#rhcsa

The laborant user is trying to use shell help tools to study for their RHCSA exam, but something is wrong on rocky-01.

Every time they run whatis or apropos, they get the same useless response:

$ whatis ls
ls: nothing appropriate.

$ apropos "list directory"
list directory: nothing appropriate.

Even man -f ls returns nothing. The man ls command itself opens a page fine, but the search and lookup tools are completely broken.

Investigate, diagnose, and fix the problem so that whatis, apropos, and man -f all return meaningful results again.

Hint 1 — Where to start

The whatis and apropos commands rely on a pre-built database of man page descriptions. Check whether that database exists on this system.

Hint 2 — Where the database lives

Look inside /var/cache/man/ — this is where the man page index database is stored. If it is empty or missing, that explains why lookups fail.

Hint 3 — How to rebuild it

The command sudo mandb scans all installed man pages and rebuilds the index database. Check the troubleshooting table in the how-to guide for the exact command.

How to Author Challenges on iximiuz Labs

Instead of providing a subpar online editing experience, iximiuz Labs offers a helper CLI tool called labctl, allowing you to use your favorite text editor (or a full-featured IDE) to write content from the comfort of your local machine.

Install labctl CLI

curl -sf https://labs.iximiuz.com/cli/install.sh | sh

This will download and install the latest version of the labctl CLI. You only need to do this once per workstation.

Authorize labctl

labctl auth login

This will open a browser window asking you to authorize labctl to access your account. You need to do it after a fresh install of labctl and repeat it whenever the auth session expires.

Pull challenge content

labctl content pull challenge rhcsa-x200101-challenge-broken-1-7a6c4e17

This will create a local copy of the challenge content in a directory named rhcsa-x200101-challenge-broken-1-7a6c4e17. You only need to do this once per challenge.

Stream your changes

labctl content push -fw challenge rhcsa-x200101-challenge-broken-1-7a6c4e17

Run this command in a separate terminal to continuously upload your changes to the server while editing the challenge in your favorite text editor or IDE.

You can also use labctl to create, list, and delete your content. Learn more about the available commands: labctl content --help

Start challenge