Resizing an LVM partition, especially reducing the root ( / ) partition, requires careful planning because the root filesystem cannot be unmounted while the system is running. To safely perform this operation, the server must be booted into a rescue environment, allowing administrators to modify disk partitions without risking data corruption. This guide explains how to safely reduce an LVM root partition using SystemRescueCd. Prerequisites Before starting: 👉 http://www.sysresccd.org/Download Step 1: Boot the Server in Rescue Mode Reboot the server and enter BIOS/Boot Menu. Step 2: Identify the Root LVM …
DKIM is an email authentication technology which uses cryptography to validate that a message was sent by an authorized source. It is a method for associating a domain name to an email message, thereby allowing a person or organization to claim some responsibility for the message. In DKIM, any sending or handling mail agent either an MTA (Mail Transfer Agent) or a MUA (Mail User Agent) can cryptographically sign mail by adding a DKIM-Signature mail header to the mail item.
Introduction CW Image Optimizer Plugin reduces image file size and improve performance using Linux image optimization programs. This will automatically and without any loss optimize the images as we upload them to your blog. It can also optimize the images that have already uploaded in the past. Because CW Image Optimizer uses lossless optimization techniques, your image quality will be exactly the same before and after the optimization. The only thing that will change is your file size.
TUN/TAP is a virtual network device that sends and receives packets to and from userspace rather than a physical interface. OpenVZ supports VPN inside a container via kernel TUN/TAP module and device.
Email authentication plays a critical role in improving email deliverability and protecting domains from spoofing. DomainKeys Identified Mail (DKIM) adds a digital signature to outgoing emails, allowing receiving servers to verify that messages are legitimate and unaltered. This guide explains how to install and configure OpenDKIM with Postfix to enable DKIM signing on a Linux server. What is OpenDKIM? OpenDKIM is an open-source implementation of the DKIM standard. It integrates with mail transfer agents like Postfix to automatically sign outgoing emails using cryptographic keys. Benefits include: Step 1: Install Required …
ls command will surely be one of the most used command while working with Linux command line. Think of a situation when your ls binary get corrupted. Is there any alternative of “ls” command. The Answer is “YES” echo does ls
Email communication remains a critical component of modern infrastructure, and organizations often require reliable and secure mail transfer systems. Qmail is an SMTP-based Message Transfer Agent (MTA) designed for Unix environments. Known for its stability, security model, and ease of configuration, Qmail is often preferred over traditional solutions like Sendmail. This guide walks through the complete process of installing and configuring a Qmail mail server along with supporting utilities such as ucspi-tcp and daemontools, followed by enabling SMTP and POP3 services. Why Choose Qmail? Qmail provides several advantages: Prerequisites Before …
A sudden increase in server load can be alarming, especially on production systems. One common and often misunderstood cause is an active RAID resync or rebuild process. When a RAID array is rebuilding, the system performs intensive disk I/O operations, which can significantly impact overall server performance. Understanding how to identify and safely manage RAID rebuild load is essential for Linux administrators. Identifying RAID Rebuild Activity The first step when investigating unexplained load spikes on a Linux server is to check the RAID status using the following command: cat /proc/mdstat …
Virtualization is the creation of a virtual version of an operating system , a server, a storage device or a network resources. Operating system virtualization uses software which allows a piece of hardware to run in multiple operating system images at the same time. There are mainly three areas of IT where virtualization is making head-roads. They are : Network virtualization Storage virtualization Server virtualization
ProFTPD is a highly configurable FTP server that offers advanced control over user authentication and access management. However, standard FTP has a major security drawback—passwords are transmitted in plain text, making them vulnerable to network sniffing. To improve security, you can configure virtual FTP users using ProFTPD’s AuthUserFiles feature. This ensures that credentials are stored securely and not tied directly to system users. Why Use Virtual FTP Users? Using virtual users in ProFTPD helps you: Step 1: Install ProFTPD First, enable the RPMForge repository (if not already configured) and install …