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Linux


Linux


Linux

Vim – Change Color Scheme for Easy Readability

April 22, 2022 Zsolt Agoston
Set the 'desert' color scheme for Vim. easier on the eyes on dark backgrounds ... [Read More]
Linux

SSH Private key Authentication to Linux on a Windows Machine

April 20, 2022 Zsolt Agoston
Learn how to use private certificate files to automatically authenticate to SSH servers. No password needed! ... [Read More]
Linux

How to Configure Static IP on Debian 10

April 15, 2022 Zsolt Agoston
Configure a static IP address on a Debian 10 server using the command line ... [Read More]
Linux

MySQL Query All Users and User Premissions

April 10, 2022 Zsolt Agoston
List all the users and user permissions in a MySQL database using the shell ... [Read More]
Linux

Proxmox Update Unauthorized Issue Fix

March 27, 2022 Zsolt Agoston
A quick tip on how to fix the Failed to fetch, unathorized error in Proxmox when trying to update the system ... [Read More]
Linux

How to Check if Linux needs Reboot after Updating?

November 23, 2021 Zsolt Agoston
Does your linux system need a reboot after an updating session? Let's find out! ... [Read More]
Linux

Use the ls command to list only a directory, NOT it’s contents in Linux

June 28, 2021 Zsolt Agoston
Learn how to get the filesystem information of a directory itself, NOT it's contents, using ls in unix ... [Read More]
Linux

How to Delete Traces from Linux History

November 25, 2020 Zsolt Agoston
So you want to delete all traces of certain commands from the Bash history? Here's how to do it! ... [Read More]
Linux

How to Flush ARP cache in Windows, Linux and MacOS

November 14, 2020 Zsolt Agoston
With certain network changes you might end up with nodes in your network having issues contacting other hosts outside of their subnet. A typical scenario is when the default gateway's IP is re-assigned to a new router and the old ... [Read More]
Linux

Ping Sweep Without Nmap with Native Tools in Linux, Windows, macOS

November 12, 2020 Zsolt Agoston
Ping sweeping is a basic technique to find active hosts on a network. You might be looking for a particular host in your infrastructure, like a network printer, or you simply want to assign a static IP to a new ... [Read More]
Linux

Fix SSH Certificate Authentication in Linux

November 3, 2020 Zsolt Agoston
A guide on how to fix SSH cert authentication when it doesn't work ... [Read More]
Linux

Create and Expand LVM Volumes – Step by Step Guide

October 27, 2020 Zsolt Agoston
Click here for a quick summary on how to create and administer volume groups and volumes in LVM ... [Read More]
Linux

How to Force cp in Linux

October 4, 2020 Zsolt Agoston
Is it familiar? This annoying confirmation prompt appears on certain linux distribution when you try to copy a file that already exists at the destination. Here's how to solve this one and for all ... [Read More]
Linux

Bash Tips for Daily Use

September 29, 2020 Zsolt Agoston
Have you ever needed to edit a config file after checking it's permissions, finding yourself typing in the same long file path twice in the shell? Or wondering how you can rerun the command you used a few steps ago ... [Read More]
Linux

How to search in VIM

September 21, 2020 Zsolt Agoston
Legend has it a dev once said: "I've been using vim for 2 years now, mostly because I cannot figure out how to exit it!" In this article we walk through the ways how to search certain words, or strings ... [Read More]
Linux

Install Postfix on CentOS for Internet email traffic

September 4, 2020 Zsolt Agoston
It's a quick guide to install a postfix server on CentOS, that can receive incoming email from the internet. In our lab we use our protectigate.com domain, and a user mailbox john@protectigate.com, who will receive our test email ... [Read More]
Linux

How to Configure NFSv4 and NFSv3 on CentOS?

August 14, 2020 Zsolt Agoston
Installing an NFS file server on linux mainly consists of three short steps: install the NFS package, then configure (or in another words export) the NFS shares and lastly set the built-in firewall to allow incoming NFS queries ... [Read More]
Linux

Mount NFS, SMB shares and local volumes in Linux | Cheat Sheet

June 24, 2020 Zsolt Agoston
This a quick guide on how to mount different type of volumes or shares in Linux. We go through the most common scenarios: local volumes, NFS and SMB shares. For each we discuss the manual way to mount them, also ... [Read More]
Linux

Kibibytes, Mebibites, Gibibites!

June 3, 2020 Zsolt Agoston
Have you ever bought a brand new SSD with 256GB on it's label, then when connecting it to a computer the storage space of only 240GB was showing? Were you taught in school that a 'kilobyte' is actually 1024 bytes, ... [Read More]
Linux

FREE SSTP VPN server on Linux with SoftEther

May 18, 2020 Zsolt Agoston
Always Hot Café needs a fast and cheap way to set up a VPN solution for it's workers. They don't want to invest in expensive hardware, or software. Also, the employees have Windows laptops and they want to use the ... [Read More]
Linux

Specifying granular UNIX file permissions using SETFACL

April 26, 2020 Zsolt Agoston
UNIX type systems use the octal file permission model, that is limited in terms of setting access permissions for specific users and groups. By default there are only three attributes to be set on files and directories: for the owner, ... [Read More]
Linux

Join RHEL or CentOS 8 to an Active Directory Domain using SSSD

April 12, 2020 Zsolt Agoston
The task for today is to join a Microsoft Active Directory domain with our CentOS box. We use the sssd package to accomplish this, first we start with a basic CentOS installation, we go through the initial setup, then the ... [Read More]
Linux

How to Setup HTTPS on a CentOS 8 Server

April 11, 2020 Zsolt Agoston
Our goal is to make our website protected, configuring the HTTPS service on it to ensure encrypted traffic between the client and our server. We utilize Let’s Encrypt’s certbot, that will create and automatically renew the publicly signed SSL certificates ... [Read More]
Linux

How to Set Up Multiple Apache Virtual Hosts on CentOS 8

April 10, 2020 Zsolt Agoston
    So what are Virtual Hosts and what are they for? John has a web server, connected to the internet with a single IP address. He has a website, called JohnBlog.com which is pointing to this web server. He ... [Read More]
Linux

How to build a basic webserver on CentOS with Apache, MySQL and PHP

April 9, 2020 Zsolt Agoston
Before You Begin Our job is really easy this time as we already have the process of installing Apache, MySQL and PHP on Debian based machines, as it is really similar to the process on RHEL based boxes. For the ... [Read More]
Linux

SSH login with certificates – NO password needed !!!

April 5, 2020 Zsolt Agoston
You might have been wondering: do I really need to type in my long password every time I SSH into a remote server, possibly making a typo and starting the password all over again without seeing any feedback on the ... [Read More]
Linux

How to Deploy automatically renewing SSL certificates on Ubuntu and Debian

April 3, 2020 Zsolt Agoston
To see how to deploy a WordPress site from scratch please check out this previous article where we went through the process step by step. In this article we set up automatic HTTPS, that means all the HTTP requests are ... [Read More]
Linux

Install WordPress on Ubuntu Linux – Step by Step

April 2, 2020 Zsolt Agoston
In this tutorial we will deploy a WordPress site for http://protectigate.com We assume that a web server is already ready for us. If you don’t have one you can check the installation process for Debian (like Ubuntu) and RHEL (CentOS) ... [Read More]
Linux

How to Build an Apache Webserver on Debian, Ubuntu Linux

April 1, 2020 Zsolt Agoston
Before You Begin A minimal installation of Debian or Ubuntu linux is the starting point, with network connectivity. L.A.M.P is an acronym, stands for the building elements of a fully working website:
  • Linux is probably the most stable and ... [Read More]
Linux

One Interface, multiple VLAN IPs on Linux

March 29, 2020 Zsolt Agoston
To make use of a trunk interface connected to our linux box with a single interface we can configure subinterfaces accessing specific VLAN segments, here we will use Debian and RHEL, assigning two subinterfaces, to each, on will use DHCP ... [Read More]
Linux

Expanding an LVM volume with a new disk

March 26, 2020 Zsolt Agoston
Time to time we can face the problem that our storage is running out of space on our Linux box. Now what options do we have? We can attach a new storage to the system and mount it in the ... [Read More]
Linux

CentOS 8 Install in Text Mode

March 25, 2020 Zsolt Agoston
Text Mode Many times it is preferable to run the CentOS linux installer in text mode, avoiding the GUI. For instance when using an older machine with less resources or when deploying a VM when console access might be limited, ... [Read More]

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