What is High Availability? A Tutorial

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High Availability

High availability is the description of a system designed to be fault-tolerant, highly dependable, operates continuously without intervention, or having a single point of failure. These systems are highly sought after to increase the availability and uptime required to keep an infrastructure running without issue. The following characteristics define a High Availability system.

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How to Install INXI on Ubuntu 18.04

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INXI is one of the best tools that offer a straightforward and comprehensive method for obtaining a wealth of information about a server with a single command.

There are a myriad of individual tools and commands that can be utilized to glean this information from a Linux system. Understanding the specific hardware that underlies a Linux server is an integral part of understanding that server’s capabilities. In this tutorial, we will cover the installation of INXI on an Ubuntu 18.04 server. It will also include some basic command-line usage of the INXI tool.

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What is Kubernetes RBAC Authorization

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What is RBAC?

Kubernetes Role-Based Access Control or the (RBAC) system describes how we define different permission levels of unique, validated users or groups in a cluster. It uses granular permission sets defined within a .yaml file to allow access to specific resources and operations.

Starting with Kubernetes 1.6, RBAC is enabled by default and users start with no permissions, and as such, permissions must be explicitly granted by an admin to a specific service or resource. These policies are crucial for effectively securing your cluster. They permit us to specify what types of actions are allowed, depending on the user’s role and their function within the organization.

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Why Is Most of My Memory Being Used?

Reading Time: 2 minutesOften we hear a lot of customers asking why, when their server is largely idle, much of their RAM appears to be in use.

When RAM is not needed for other functions, your server will load frequently-accessed files into memory in order to read them more quickly. When a file is loaded into RAM, the server can access the information orders of magnitude faster than from disk. A modern SSD disk can read files at up to around 500-700 MB/second, if the files are in sequential units. However, RAM can be read at GB/second rates; or even tens of GB/second.

If the RAM becomes needed for another function, these files are quickly flushed out of memory, and the RAM becomes available for other tasks. Continue reading “Why Is Most of My Memory Being Used?”

How to Enable Remote MySQL Connections in cPanel

Reading Time: 2 minutesRemote MySQL connections are disabled by default in cPanel servers because they are considered a potential security threat. Using the tools in the Web Host Manager (WHM) and the domain-level cPanel interface (usually http://domainname.com/cpanel) remote hosts can be added which the server allows connecting to the MySQL service.

Before using either of the following techniques, you will need to open up port 3306 in your server’s firewall.

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How to Display (List) All Jobs in Cron / Crontab

Reading Time: 2 minutesServers can automatically perform tasks that you would otherwise have to perform yourself, such as running scripts. On Linux cloud dedicated servers or VPS servers, the cron utility is the preferred way to automate the running of scripts. In this article, we’ll cover how to view the jobs scheduled in the crontab list. For an introduction to Cron check-out our KB: How To: Automate Server Scripts With Cron. Knowing how to set up crontab is an important skill, but even if you’re not editing these knowing how to view them is important as well. Continue reading “How to Display (List) All Jobs in Cron / Crontab”

How To: Upgrade Apache and PHP using cPanel’s Easyapache

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Note:
Please note that this article is considered legacy documentation because EasyApache 3 has reached its end-of-life support.

If you run a cPanel server, and need to upgrade your Apache or PHP version, cPanel provides the Easyapache tool to make these updates a breeze. While it can be run from WHM, it is generally preferred to run it from the command line.

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Apache Error: “semget: No space left on device”

Reading Time: < 1 minuteIf Apache fails, and will not successfully start again, check the error log. If you see an error similar to the following, it could indicate that your server has run out of semaphores.

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WordPress Tutorial 3: Install a Plugin, Theme, or Widget

Reading Time: 3 minutesThis is part 3 in an ongoing series on WordPress. Please see Part 1: WordPress Tutorial 1: Installation Setup and Part 2: WordPress Tutorial 2: Terminology and Part 4: WordPress Tutorial 4: Recommended WordPress Plugins. Please note that this guide is primarily intended for customers utilizing a Linux server running cPanel. If you do not have a Linux server with cPanel please see the documentation at wordpress.org for further assistance.

The three most common changes you will make to your website involve the look (themes), the functionality (plugins), and modular elements (widgets).
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