In-depth HOWTO on Linux kernel configuration

While we talked before about kernel compilation and configuration, we focused on the general idea. This time we want to dig deeper into the configuration part, giving you useful advice you will need when tailoring a kernel to perfectly match your hardware.
The main idea behind this is that you will need to know your hardware extremely well in order to have a kernel built exactly for it. At the beginning we will cover what you will need in order to compile your kernel and after that we move into Linux kernel configuration, compilation and installation. Please note that this time it’s not very important if you compile a vanilla kernel or a distribution kernel. We will however, recommend a “modus operandi”, which of course does not mean that you have to follow. After reading this guide you will be able to decide what suits you best. We expect some moderate knowledge about Linux system internals and development tools.

What you will need

From now on, as stated before, we will show you how we do this, so everything you’ll read will be specific to our system, unless stated otherwise. Typing ‘du -h’ in our kernel source tree shows 1.1G. This is after we typed ‘make clean’. In short, we’d say you better have at least 2.5G available for the kernel tree, since code gets added constantly and object files take quite some space. Also /lib/modules/ will use a lot of disk as time passes, and, if you have a separate /boot partition, that may get crowded too.

Of course, after you configure the kernel, you’ll want to compile it, so the usual suspects must be present : make, git, gcc, the readline library for menuconfig… Speaking of git, you might have heard about the recent break of kernel.org, so if you try to clone the usual location or try to pull, you will get

$  git pull
fatal: Unable to look up git.kernel.org (port 9418) (Name or service not known) 

What you can do is use the new, temporary location of the git tree as announced by Linus Torvalds :

 $ git pull git://github.com/torvalds/linux.git 

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Making use of your older hardware with Linux/BSD

Introduction

Some of you may wonder what is the purpose of this article. First, because hardware nowadays is pretty cheap, you don’t need older hardware anymore. Second, there are some articles across the Internet dealing with this already. The answer to the first problem is: well, you’ll see in the article. The answer to the second is we have some experience with older hardware first-hand, and we found it to be very useful to this day, so we want to share this with you. Older hardware, PC or not, is to be found everywhere, sometimes for free, and you can get to it easily. You will get some ideas from this article, but of course we don’t say the following list is exhaustive. Only your imagination sets the limit. The only knowledge we expect from you is to have some idea what you want to do. If you don’t yet, our article may be of help.

The hardware

Before we start, there are some variables that need some comments. First, the word “older” means different things for different people. To some, it may mean a 6 year-old AMD Athlon processor and 1GB of RAM. To others, “older” may be a PentiumII with 128 MB RAM. This article is mainly focused on the latter part, meaning really old hardware that’s still of some use with Open Source operating systems. Of course, if you have something more powerful, even better. The other variable is the hardware. People can find an old SPARC machine with < 100$ that is still usable, depending of course on what you want to do with it. The places you can find such machines, SPARC, SGI or Intel-based are Ebay, some local shop that sells older computers or even your friendly sysadmin that can’t wait to get rid of old machines. Take note that non-Intel machines will be more expensive, so think twice if you really need some exotic piece of hardware.

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main

Introduction to the lsblk command

Lsblk is a very nice utility installed by default on practically all Linux distributions: we can use it to retrieve a vast range of information about all the block devices attached to the system. In this article we will see how it works and how to use it.

In this tutorial you will learn:

  • How to use the lsblk utility to retrieve information about block devices
  • What is the meaning of the columns displayed in the default utility output
  • How to specify the columns to be displayed and format the output as json or as a list
  • How to display information about a specific device.

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Formatting SD or USB disk on Linux

Formatting SD or USB disk under Linux

In this guide, we go through the steps to format an SD or USB disk in Linux. This can be done via GUI or command line, and we’ll cover the process for both. The guide will be applicable regardless of what Linux distribution you’ve decided to use, especially the command line method.

This will wipe all the data from your USB or SD disk and get it ready for use under Linux or another system. It’s also used to clear the device before creating a bootable live USB drive.

In this tutorial you will learn:

  • How to format an SD or USB disk via GUI
  • How to format an SD or USB disk via command line

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Using webcam on Manjaro Linux

How to test Webcam on Manjaro Linux

Webcam setup on Manjaro Linux and other user-friendly Linux distributions should be automatic. You can usually plug in your webcam and have instant access to it. If you have a built-in camera, that should also work without any extra configuration.

In this guide, we’ll go over testing a webcam on Manjaro and give some troubleshooting pointers in case yours isn’t being detected automatically.

In this tutorial you will learn:

  • How to test webcam

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Testing a microphone in the settings menu on Manjaro Linux

How to test microphone on Manjaro Linux

In this tutorial, we guide you through the process of testing a microphone on Manjaro Linux. Microphones should work out of the box on Manjaro and other user-friendly Linux distributions, but sometimes you may need to select the right device from the audio settings menu. This guide will also show how to record sound with a GUI application.

In this tutorial you will learn:

  • How to test microphone and select input device
  • How to record audio clips

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Setting up a printer in Manjaro Linux

How to setup printer on Manjaro Linux

Printing in Manjaro and the majority of other Linux distributions is handled through the CUPS system. After installing Manjaro Linux, setting up a printer is one of the first tasks that many users will need to tackle.

In this guide, we will guide you through the process of setting up a printer on Manjaro Linux. CUPS makes the process a lot more painless than many other alternative methods, so that’s what we’ll be using.

In this tutorial you will learn:

  • How to install and enable printer software (CUPS)
  • How to configure printer automatically with HP Device Manager or CUPS
  • How to manually setup a printer
  • How to access print jobs, printers, and CUPS documentation

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How to benchmark Disk performance on Linux

How to benchmark Disk performance on Linux

Just bought the latest and greatest – and especially fastest – SDD? Or upgraded your phone’s microSD memory card? Before you start using your shiny new hardware, you may want to run a performance check against the drive. Is the write and read speed up to manufacturer’s specifications? How does your performance compare with that of others? Is that 1TB flash drive you bought on an auction site from China really as fast as the listing said it was? Let us find out!

In this tutorial you will learn:

  • What CLI (Command Line Interface: your Bash or other terminal environment) disk performance measuring tools are available
  • What GUI (Graphical User Interface: your desktop environment) disk performance measuring tool we recommend
  • How to effectively measure disk performance in a straightforward manner
  • Discover and learn with various disk performance measuring examples
  • How to get a sense for the quality of disk/flash hardware you own

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How to Reduce hard drive’s acoustic noise level

Most of the non-SSD hard drives allow for a noise reduction by decreasing head movement speed while accessing data. This ability is called Automatic Acoustic Management or AAM. This tutorial will show how to manipulate AAM values to reduce or increase head movement thus directly affect hard drive’s noise level.

The best tool for this job is hdparm. hdparm is available for all major Linux distributions and is available for install via hdparm package. If hdparm command is not available on your system yet, you can install it using following linux commands:

UBUNTU/DEBIAN
# apt-get install hdparm
OR
FEDORA/RED HAT
# yum install hdparm

First find a correct block device for a hard drive you would like to work with. This can be done by:

]$ lsscsi -g
[2:0:0:0]    disk    ATA      HTS721060G9SA00  MC3I  /dev/sda   /dev/sg0

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Ubuntu 20.04 System Requirements

Ubuntu 20.04 System Requirements

Considering downloading Ubuntu 20.04 but need to know the system requirements? In this article, we’ll go over the minimum recommended system requirements for running Ubuntu 20.04 Focal Fossa. Whether you want to install it on a PC or as a virtual machine, we’ll help you make sure you have the required hardware.

Ubuntu is an inherently lightweight operating system, capable of running on some pretty outdated hardware. Canonical (the developers of Ubuntu) even claims that, generally, a machine that can run Windows XP, Vista, Windows 7, or x86 OS X can run Ubuntu 20.04 perfectly fine. Let’s take a closer look at the hardware requirements below.

In this tutorial you will learn:

  • System requirements for Ubuntu 20.04 Desktop
  • System requirements for virtualized Ubuntu 20.04 Desktop
  • System requirements for Ubuntu 20.04 Server
  • Lightweight GUI alternatives to GNOME

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