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Enable One Time Password in Ubuntu 24.04 for SSH or Local Login

Last updated: September 11, 2024 — Leave a comment

This tutorial shows how to enable One Time PassWord in Ubuntu 24.04 for either local or remote SSH login.

One Time PassWord, OTPW in short, is a PAM module which is useful for allowing a user to login public or shared computer/server using a single-use password, that works only for one time.

By generating a list OTPW passwords, and configuring your system to allow OTPW logins, it will ask random one of the OTPW passwords on every login. And, that password will never work again once logged in successfully with it.

In Howtos password, security, ssh

Set up Authentication Key for Remote SSH Login in Ubuntu 24.04

Last updated: September 8, 2024 — Leave a comment

This is a simple tutorial shows how to disable password authentication, and use SSH key instead for remote login to remote Ubuntu Server or Desktop.

SSH (Secure Shell) is a popular and secure way to login remote servers and/or transfer data between local and remote machines. When you try to SSH to a remote server, it usually asks for user password for authentication.

However, passwords are not the most secure. They are generally either not complex or long enough to protect from attacks, or hard to remember and type again and again on every connection.

To be more secure and also save your time, the secure key authentication is a good choice. And, here’s how to set it up step by step.
Continue Reading…

In Howtos ssh

How to Share your USB Device in Ubuntu 24.04 over LAN

Last updated: September 5, 2024 — Leave a comment

This tutorial shows how to share your USB device, e.g., USB mouse/keyboard, USB drive, webcam, and speaker, in Ubuntu so you can access remotely from other computers/laptops.

Linux Kernel includes a command line tool called USB/IP, allowing to share USB devices between computers with their full functionality. So, a computer can use remote USB devices as if they were directly attached.

If you just want to share USB mouse & keyboard between computers, then Barrier is a good choice. But for webcam, usb drive, printer (through it usually has option to do the job), and other general USB devices, this tutorial will show you how.

In Howtos network, USB

Remap Keyboard Keys in Ubuntu 24.04 without 3rd Party Apps

Last updated: September 3, 2024 — Leave a comment

This is a step by step tutorial shows how to manually remap (or disable) keyboard keys in Ubuntu without using any third-party apps.

There are a few free open-source applications that can re-map your mouse, keyboard, and other input devices keys in Linux. As far as know, they include input remmaper and AntiMicroX.

For GNOME, the default desktop for Ubuntu and Fedora Workstation, there’s popular GNOME Tweak tool (available in AppCenter/GNOME Software) with options to remap Ctrl, Alt, and Caps Lock keys.

GNOME Tweaks

In Howtos keyboard

Disable Ubuntu Pro Updates in Ubuntu 24.04 Software Updater

Last updated: September 1, 2024 — 2 Comments

This tutorial shows how to disable “Ubuntu Pro” security updates in both apt command output and Software Updater dialog in Ubuntu 24.04 LTS.

Ubuntu Pro is a comprehensive subscription for Extended Security Maintenance (esm in short), which also enables another 5-year support for Ubuntu LTS releases. And, it’s free for personal and small-scale commercial use on up to 5 machines.

In all current Ubuntu LTS releases, the apt upgrade command and “Software Updater” display the Ubuntu Pro updates, which is quite annoying. Rather than enable Ubuntu Pro, here’s how to get rid of the ads step by step.

Ubuntu Pro updates in Software Updater and terminal

In Howtos apt

How to Upgrade to Ubuntu 24.04.1 from Ubuntu 22.04

Last updated: September 5, 2024 — Leave a comment

Ubuntu announced the first point release of Ubuntu 24.04 LTS few days ago with lots of bug-fixes and performance improvements. It’s time to upgrade to the new LTS, for users who were worrying about the stability issues.

Ubuntu 24.04 is the current Long Term Support (LTS) release with 5 years of standard support until 2029, another 5 years Ubuntu Pro support until 2034, as well as legacy support until 2036. It features Linux Kernel 6.8, GNOME Desktop 46, and various other changes, see the official release note for details.

The new LTS had various upgrade issues, and stability / performance issues, for apps and hardware including Nautilus file manager, the new tiling assistant, NVIDIA on Wayland, Pipewire sound server, hybrid GPU machines, Remmina RDP client, online accounts, cursor themes, and more! They are all fixed in the release of Ubuntu 24.04.1.

Ubuntu 24.04 Desktop

In Howtos ubuntu 24.04

Enable Zram in Ubuntu for Better Performance on Limited RAM

Last updated: August 28, 2024 — 2 Comments

This is a step by step tutorial shows how to enable zram Kernel module and use as Swap device for better system performance in Ubuntu 24.04 PC/laptop with limited RAM.

As you may know, Ubuntu usually includes a swap space. It works like MS Windows’ “virtual memory”, that uses the hard disk for additional memory when there is not enough physical RAM for all tasks request.

Swap on disk however is slow, which will slow down the overall system performance. So, Linux introduced “zram” and “zswap” kernel modules to improve performance for computers with small amount of RAM.

In Howtos RAM, zram, zswap

How to Enable Zswap for Ubuntu 24.04 PC with Limited RAM

Last updated: September 6, 2024 — 3 Comments

This tutorial shows how to enable zswap kernel module to increase usable RAM in your Ubuntu computer or laptop.

As you know, Ubuntu Linux usually includes a swap space (either disk partition or swap file) on the disk. It can be used for hibernation, and as extended memory space. When the system needs more memory resources and the RAM is going full, then the inactive pages in memory are moved to the swap space.

Swap space can be helpful for computers with limited RAM. But, it’s slow! Too much swap in use will slow down the overall system performance.

As workarounds, Linux includes 2 kernel modules: zram and zswap. Instead of moving inactive pages from memory to disk (swap space), they do similar things by compressing the data into dynamically allocated RAM space.

As the data is compressed, it takes less physical memory space which makes your RAM even more usable. While, keeping the system running smoothly because reading from compressed data in RAM is usually faster than reading from swap on disk.

In Howtos RAM, zswap

Disable Keyboard, Mouse, or Lid from Waking up Your Ubuntu PC

Last updated: August 24, 2024 — Leave a comment

This tutorial shows how to enable/disable Keyboard, Mouse, Lid Open, and/or other devices events from waking up your Ubuntu PC or laptop from sleep.

By default, open laptop lid, press any key on keyboard, or press sleep button can wake up your computer from suspend or hibernation state. If you want, you can configure Ubuntu to ignore certain wakeup triggers that you don’t want.

image from pixabay.com

In Howtos hibernate, suspend

How to Control ThinkPad Fan Speed in Ubuntu 24.04

Last updated: September 2, 2024 — 5 Comments

This is a step by step beginner’s guide shows how to control the fan speed in Lenovo ThinkPad laptop running Ubuntu 24.04.

The fan speed control solution differs depends on computer manufacturers. For my ThinkPad T480s, fan is usually not spinning when doing the basic web browsing and other light works.

But if you want, it’s easy to set a fixed fan speed, or adjust the speed automatically according to the core temperature.

In Howtos fan speed, thinkpad