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Make first deb-src package by example cri-o

Configuring Linux *Open source **nix *Development for Linux *
Tutorial


Overview


Once every true-linux engineer gets a trouble: there is no any software in his distro or it's built without needed options. I am keen on the phrase: "Only source control gives you freedom".


Of course, you can build this software on your computer without any src-packages, directly (with simplification: configure, make, make install). But it's a non-reproducible solution, also hard for distribution.


The better way is to make distro-aligned package that can be built if needed and that produces lightly distributed binary-packages. It's about debian-source packages(debian,ubuntu,etc), pkgbuild (for arch), ebuild for gentoo, src-rpm for red hat-based, and many others.


I will use cri-o like a specimen.


Before reading the text below I strongly recommend to get familiarized with the official Debian policy manual placed here and debhelper manpage.


Also you will be required to setup some variables like DEBMAIL and DEBFULLNAME for proper data in changelog and other places.

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Total votes 1: ↑1 and ↓0 +1
Views 360
Comments 1

An Antidote to Absent-Mindedness, or How I Gained Access to an OpenShift Node without an SSH Key

Иннотех corporate blog System administration **nix *DevOps *Openshift *
Translation

Typically when a Node falls out of the OpenShift cluster, this is resolved by simply restarting the offending element. What should you do, however, if you’ve forgotten the SSH key or left it in the office? You can attempt to restore access by using your wit and knowledge of Linux commands. Renat Garaev, lead developer at Innotech, described how he found the solution for this riddle and what was the outcome.

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Rating 0
Views 4.7K
Comments 0

Introducing into calamares bootloader

Configuring Linux *Open source **nix *Development for Linux *Software
Tutorial


Overview


Sometimes all of us need to make a graphical installer for one's own linux distro. It goes without saying that you are able to use a distro-specific installer like Anaconda for RedHat-based or DebianInstaller for debian-based. On the other hand Calamares is a graphical installer which is not aligned with only one package manager.


I want to share my experience how to make a universal install solution with GUI. I did not find any complete article about it, hence, I reinvented the wheel.

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Total votes 2: ↑2 and ↓0 +2
Views 2.2K
Comments 0

LVM Thinpool Restore

Configuring Linux **nix *
Sandbox

Hi everyone, today I will tell how I restored a defunct LVM thinpool. Unfortunately I could not find any howtos or manuals on the internet, so maybe this one will help someone in a similar situation.

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Total votes 2: ↑2 and ↓0 +2
Views 1.8K
Comments 0

Controlling Brushless Motors using a Linux computer or a PLC

*nix *SCADA *Computer hardware DIY Electronics for beginners
Tutorial

In this video, we will look at how to connect brushless motor controllers to a Linux computer. Specifically, we will use a computer running Debian. The same steps would work for Ubuntu Linux and other Linux distributions derived from Debian.

I've got a small sensorless brushless motor, and a bigger brushless motor with a built-in absolute encoder. Lets look at how to control those from my Debian Linux computer. Servosila brushless motor controllers come in several form factors with either a circular or a rectangular shape. The controllers come with a set of connectors for motors and encoders as well as for USB or CANbus networks.

The controllers can be powered by a power supply unit or by a battery. To spice up my setup, I am going to use a battery to power the controllers and thus their motors. The controllers need 7 to 60 volts DC of voltage input. If I connect the battery, the controllers get powered up. The small LED lights tells us that the controllers are happy with the power supply.

We need to connect the brushless motor controllers to the Linux computer. There are two ways to do that - via CANbus or via USB. Lets look at the USB option first. A regular USB cable is used. Only one of the controllers needs to be connected to a computer or a PLC.

Next, we need to build an internal CANbus network between the controllers. We are going to use a CANbus cross-cable to interconnect the controllers. Each controller comes with two identical CANbus ports that help chain multiple controllers together in a network. If one of the interconnected brushless motor controllers is connected to a computer via USB, then that particular controller becomes a USB-to-CANbus gateway for the rest of the network. Up to 16 controllers can be connected this way via a single USB cable to the same control computer or a PLC. The limit is due to finite throughput of the USB interface.

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Total votes 4: ↑3 and ↓1 +2
Views 1.7K
Comments 0

The Implementation of a Custom Domain Name Server by Using С Sockets

*nix *DNS *C *SQLite *
Sandbox

We describe the implementation of a custom Domain Name System (DNS) by using C socket programming for network communication, together with SQLite3 database for the storage of Internet Protocol (IP) for Uniform Resource Locator (URL). Then we provide a performance analysis of our implementation. Our code is available publicly [1].

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Total votes 5: ↑4 and ↓1 +3
Views 2.1K
Comments 0

Using kconfig for own projects

Configuring Linux **nix *Development for Linux *

Intro


Every Linux professional write scripts. Someеimes light, linear. Sometimes complex script with functions and libs(yes, you can write your bash-library for use in other scripts).


But some of the scripts need a configuration file to work. For instance, I wrote a script that builds the ubuntu image for pxe, and I need to change the build process without build-script changes. The best way to resolve this task is to add configuration files.

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Total votes 2: ↑2 and ↓0 +2
Views 5.4K
Comments 3

Porting packages to buildroot using the Zabbix example

Configuring Linux *Open source **nix *Development for Linux *Software
Tutorial


The basics of porting


Originally, Buildroot offers a limited number of packages. It makes sense — there is everything you need, but any other packages can be added.


To add a package, create 2 description files, an optional checksum file, and add a link to the package in the general package list. There are hooks at different stages of the build. At the same time, Buildroot can recognize the needed type of packages:

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Total votes 2: ↑2 and ↓0 +2
Views 3.4K
Comments 0

Safe-enough linux server, a quick security tuning

Information Security *System administration **nix *Cloud computing *Server Administration *
Tutorial
Sandbox
The case: You fire up a professionally prepared Linux image at a cloud platform provider (Amazon, DO, Google, Azure, etc.) and it will run a kind of production level service moderately exposed to hacking attacks (non-targeted, non-advanced threats).

What would be the standard quick security related tuning to configure before you install the meat?


release: 2005, Ubuntu + CentOS (supposed to work with Amazon Linux, Fedora, Debian, RHEL as well)


image

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Total votes 7: ↑6 and ↓1 +5
Views 2.2K
Comments 0

How I fix cups-printing in Buildroot

Configuring Linux *Open source **nix *Development for Linux *

image


Intro


Like I said earlier in previos articles, Buildroot is a great system for embedded Linux development. But sometimes strange things can happen.


Once upon a workday, I got the following task: add printing system in firmware (Kraftway terminal Linux next generation). Ok, so I had to add cups + cups filter and to build firmware. I set a postscript-printer and got an error "Filter failed". Trivial tasks turned into serious work.


In this article, I wrote my own way of solving this problem. It may be useful for other developers and IT-specialist and, also, for a deeper understanding of the Buildroot.


If you are a Buildroot beginner, I recommend reading my previous articles.


Update 1 may 2020


Revisioned versions of this patches applied to master.

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Total votes 2: ↑1 and ↓1 0
Views 1.6K
Comments 0

buildroot — my own experience with multi-platform distro creation

Configuring Linux *Open source **nix *Development for Linux *

Introduction


In my previous article (Monitor linux) I wrote, what is this distro and how it works. Now i will write how to do it. It's may be interesting for everyone, who want to study buildroot.


Target goals


The result we get from article is the following:


  • Firmware (non-volatile image with restorable config)
  • Easy management via web-interface
  • Cross-platform (qemu x86_64, arm-based SBC like rasberry 4, beagle bone black and asus tinker board)
  • Support without extra effort
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Total votes 8: ↑6 and ↓2 +4
Views 4.2K
Comments 2

Monitor linux — cross platform firmware with zabbix server

Open source *IT Infrastructure **nix *Development for Linux *Development for Raspberry Pi *

About


This is small cross-platform linux-distro with zabbix server. It's a simple way to deploy powerful monitoring system on ARM platfornms and x86_64.


Worked as firmware (non-changeable systemd image with config files), have web-interface for system management like network settings, password and other.


Who is interested


  • System admins/engineers who need to fast deploy of zabbix server.
  • Everyone, who want to deploy zabbix on ARM.
  • Enthusiasts
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Total votes 3: ↑3 and ↓0 +3
Views 1.8K
Comments 0

Fast and effective work in command line

*nix *Shells *
Translation

There are a lot of command line tips and trics in the internet. Most of them discribe the trivials like "learn the hotkeys" or "sudo !! will run previous command with sudo". Instead of that, I will tell you what to do when you have already learned the hotkeys and know about sudo !!.

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Rating 0
Views 2.2K
Comments 2

Down the Rabbit Hole: A Story of One varnishreload Error — part 1

*nix *Shells *Debugging *DevOps *

After hitting the keyboard buttons for the past 20 minutes, as if he was typing for his life, ghostinushanka turns to me with a half-mad look in his eyes and a sly smile, “Dude, I think I got it.


Look at this” — as he points to one of the characters on screen — “I bet my red hat that if we add what I’ve just sent you here” — as he points to another place in the code — “there will be no error anymore.”
Slightly puzzled and tired I modify the sed expression we’ve been figuring out for some time now, save the file and run systemctl varnish reload. Error message gone…


“Those emails I’ve exchanged with the candidate,” my colleague continues, as his smile changes to a wide and genuine grin, “It suddenly struck me that this is the very same exact problem!”

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Total votes 4: ↑3 and ↓1 +2
Views 905
Comments 0

Apply Nix-Shell environment in Visual Studio Code

*nix *Visual Studio *Development for MacOS *Development for Linux *
Tutorial


A lot of developers faced a problem with packages hell on their workstation. After a couple of months with experiments, including different languages and toolchains, I installed Elixir, Haskell-stack, Node.js/NVM, and other various stuff. Most exciting things happen when you need different versions of the same package for different projects. Humanity already invented a different solution for creating an isolated environment and switch them when needed. We are using NVM to manage Node.js versions, Python Virtual Env for selecting Python stuff versions or Docker for creating OS inside an OS. But none of the solutions satisfy all my requirements for the isolated development environment.
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Total votes 7: ↑7 and ↓0 +7
Views 4.7K
Comments 0
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