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Introduction to CSF/LFD Notifications

Last Updated: October 2, 2023

Category: Courses
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ConfigServer Security & Firewall (csf) with Login Failure Daemon (lfd) is “A Stateful Packet Inspection (SPI) firewall, Login/Intrusion Detection and Security application for Linux servers.”official page)) This comes pre-installed on our cPanel servers and has many useful features to assist you with detecting events which might be indicative of security issues in your server. If it […]

DNS Records Explained

Last Updated: November 18, 2021

Domain Name System (DNS) records are used to translate and store information relating to web hosting such as website IP addressing, domain name and subdomains associated, web servers, mail servers and a range of other resources that you wish to access or have accessed by others. Name Servers are used to respond to requests, keep […]

Introduction to POP3 & IMAP

Last Updated: September 23, 2021

In this article; we’ll be going over the differences between POP3 and IMAP, as well as their use-case scenarios. One of the first things you should know is that both of these are what is called “Email Protocols”. IMAP (Internet Message Access Protocol) POP3 (Post Office Protocol) These services are used for communication between a […]

Testing Remote SMTP / Mail Server Connections

Last Updated: December 8, 2021

Category: Getting Started
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When attempting to resolve mail server errors/issues, being able to test the connection to a remote SMTP server is a critical step. Testing a remote SMTP / mail server connection should be done from both a local machine (computer) and the server experiencing the issue. If a connection can be made from both locations, the […]

How can I see a list of emails in exims queue from the command line?

Last Updated: January 23, 2026

Category: Getting Started
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If you already know how many emails are in the Exims queue and want to see certain short information regarding each email in the queue, you can print a list of the emails currently queued by performing this command: Check out this screen shot for an example: Reviewing an example from that output: Let’s break […]

Libgomp thread creation error and how to fix it

Last Updated: March 10, 2023

While running any website such as WordPress that takes advantage of server applications such as ‘ImageMagick’ you may occasionally have an environment where you’ll receive an error upon uploading images. As such, when you attempt to upload an image you’ll be met with the following error message: These particular errors are a result of environment […]

What is Memcrashed and how do I fix it?

Last Updated: January 23, 2026

Memcached Memcached is a memory object caching system for speeding up dynamic web applications… It’s open source and has been designed to work with a large number of open connections. Database calls, API calls, or page rendering are a few examples of the arbitrary data results that are stored in memory to alleviate database load. One can […]

PHP OPcode Cache Install Guide

Last Updated: January 23, 2026

Category: Guides
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Overview Each time when PHP script executes on the server it goes through the following stages: tokenizing, parsing, compilation, and interpretation. PHP opcode caching allows skipping the first 3 stages by storing pre-compiled scripts in shared memory and reusing them. This significantly increases the performance of running PHP scripts. 
 It is important to know […]

Enable PHP Error Logging for Debug Testing

Last Updated: October 18, 2021

PHP error logging for your site is an optional level of logging that can be enabled to log errors that occur with PHP code. There are several reasons you may choose to enable PHP error logging. You may want to enable PHP error logging if you’re actively developing your site to aid in troubleshooting. If […]

How to use Dynamic DNS to automatically whitelist your IP?

Last Updated: September 20, 2021

Category: Guides
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Dynamic DNS offers a resolution to a common problem that many users have. ISP’s constantly change their IP, and for one reason or another, they get blocked by their server’s firewall. Often, it’s not the user’s fault. Its not that they are logging in 40 times with the wrong password, but rather they’ve simply exceeded the firewall’s […]