Introduction to Polkit

Introduction to Polkit: Navigating Authorization Frameworks in Linux

Polkit is an authorization framework installed on every modern Linux distribution: it provides API which allow privileged applications to expose services to unprivileged subjects. Communications with Polkit happens over D-Bus, which is an IPC (Interprocess Communication) system; to understand how the former works, we have to get a grasp of how the latter is implemented, first.

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How to configure Certificate Authority on Ubuntu/Debian

How to configure Certificate Authority on Ubuntu/Debian

A Certificate Authority plays a vital role in ensuring and verifying secure connections between clients and servers. When you try to connect to a remote server – let’s say a website, for example – how does your system know that it is connecting to the right place? After all, there is nothing stopping any rogue system from claiming itself as a website which it is actually not. This is where certificate authority servers come into play, by helping our client system verify that we are connecting to the intended server. This particular example is in the context of a website connection, so would involve the HTTPS protocol, but certificate authorities can also be used to authenticate other types of connections, such as VPN.

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Step-by-Step Guide: Adding Certificates to Ubuntu's Trusted Authorities

Step-by-Step Guide: Adding Certificates to Ubuntu’s Trusted Authorities

In today’s digital landscape, we must be careful to authenticate our network connections to remote servers. To help keep us secure, we use certificates that allow us to verify connections between clients and servers. A Certificate Authority is a crucial part of this process, as it is responsible for issuing the certificates to clients and servers, and verifying the devices that are trying to establish secure connections to each other.

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How to change username on Linux

How to change username on Linux

Changing a Linux account’s username is one of those user management tasks that can seem confusing or tricky at first, as it is not something that we need to do every day. Since so many settings are tied directly to an account’s username, it is generally not recommended to ever change it. But, if we find ourselves in a situation where the the username of an account absolutely needs to be changed, then we are not completely out of options.

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Setting the Root Password on Ubuntu 24.04 Linux

Setting the Root Password on Ubuntu 24.04 Linux

When managing an Ubuntu 24.04 system, it’s essential to understand the security and administrative practices that come with it. By default, Ubuntu does not set a root password and encourages the use of the sudo command for administrative tasks. This approach enhances security by limiting the use of the root account. However, there are scenarios where having a root password is necessary. This guide will walk you through the process of setting a root password on Ubuntu 24.04, ensuring you can do so securely and efficiently.

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How to Add a User to Sudoers in Ubuntu 24.04

Ubuntu, a popular Linux distribution, is widely used for its stability, security, and user-friendly interface. As you manage users on your Ubuntu 24.04 system, you might encounter situations where you need to grant administrative privileges to certain users. This guide focuses on how to add a user to the sudoers list in Ubuntu 24.04, a crucial step in managing user permissions and system security.

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introduction to proxmox backup server

Introduction to Proxmox backup server

Proxmox backup server is a free and open source, enterprise-level backup solution. It is implemented as a dedicated Linux distribution based on Debian, and supports essential features like deduplication and encryption. We can use it as a solution to back up and restore virtual machines, containers and physical hosts.

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Quick Guide to Securely Erasing Files in Linux

Quick Guide to Securely Erasing Files in Linux

Did you know that deleted files can be recovered rather easily, at least shortly after deletion? This is because deleting files does not actually erase the data, but simply tells the drive that the previously used space is now free. Until new data gets written to those blocks, the old files are still there and can be recovered with certain software.

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How to show/check for open ports on Ubuntu Linux

How to show/check for open ports on Ubuntu Linux

Checking for open ports on Ubuntu Linux is an essential part of security administration. Some Linux software works by listening for incoming connections. A simple example would be a web server, which handles user requests on HTTP port 80 or HTTPS port 443 whenever someone navigates to a website. As a Linux administrator or user, it’s important to always know which ports of your system are open to the internet. Otherwise, you could be unaware of outside connections being made to your computer, which consumes bandwidth and resources, along with being a potential security vulnerability.

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Allow SSH root login on Ubuntu 20.04 Focal Fossa Linux

Enable SSH root login on Ubuntu 20.04 Focal Fossa Linux

SSH (Secure Shell) is used to handle network services securely over an unsecured network. Some examples include: remote command-line, login, and remote command execution. Normally to log into SSH, it must be done as a normal user, and then you can elevate to the root user after logging in. But it is possible to bypass this behavior with a simple config edit. In this tutorial, you will learn how to enable SSH root login on Ubuntu 20.04 Server/Desktop.

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How to increase the security of Systemd services

How to increase the security of systemd services

Nowadays all major Linux distributions adopted Systemd as their init system/service manager. Creating a systemd service is just a matter of writing a “.service” unit in the appropriate directory, and manage it using the systemctl utility. When starting a service, or launching a process in general, we want to make sure it runs with the lowest possible set of privileges it needs to accomplish the task. Systemd provides a series of options we can be use to fine-tune the behavior of a service, granting or denying privileges in a granular way, and ensuring a certain level of isolation from the rest of the system.

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how to install keepassxc on linux

How to install KeePassXC on Linux

KeePassXC is a free and open source application we can use to safely manage our passwords and sensitive data. It can store usernames, passwords, URLs, and even file attachments. Data is encrypted and stored locally, in a “kdbx” file: this is the ideal solution if we don’t want to store sensitive information in the cloud.

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