Command-not-found package?

Hi, happy holidays and wish you all a great 2022!

While doing a routine maintainance on my VPS (Ubuntu Server 20.04) I saw this package was available for update.

The following packages will be upgraded:
  command-not-found libnss-systemd libpam-systemd libsystemd0 libudev1
  openssh-client openssh-server openssh-sftp-server python3-commandnotfound
  systemd systemd-sysv systemd-timesyncd udev

However I could not found any information online about any package called “command-not-found” nor it seemed to be installed in my machine. Although to be fair I only checked if it existed as a command by running which and the man pages for it.

Do you guys have any idea what it is and what it does, and also what python3-commandnotfound which I assume is somehow related? And how could I upgrade some packages of my choice rather than upgrade all of them listed here? Thanks!

It’s for when you either type a command that isn’t installed, or mis-type a command. It tries to figure out, using the package catalog, what command you might have been trying to type and/or what package(s) would provide it.

$ apt show command-not-found
Package: command-not-found
Version: 20.04.5
Priority: standard
Section: admin
Origin: Ubuntu
Maintainer: Michael Vogt <>
Original-Maintainer: Zygmunt Krynicki <>
Installed-Size: 36.9 kB
Depends: python3-commandnotfound (= 20.04.5)
Suggests: snapd
Task: standard
Phased-Update-Percentage: 70
Download-Size: 5,244 B
APT-Manual-Installed: yes
APT-Sources: focal-updates/main amd64 Packages
Description: Suggest installation of packages in interactive bash sessions
 This package will install a handler for command_not_found that looks up
 programs not currently installed but available from the repositories.

You don’t have to accept the list; you can copy-paste or just type the ones you want in your apt get command.


Thank you it’s good to know how to check for packages in the future using apt show! I’ve only ever used it a few times to check versions not descriptions

1 Like