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Recent Posts

• AlmaLinux 9 System and Process Monitoring
  An essential part of running and administering an AlmaLinux 9 system involves monitoring the overall system health regarding memory, swap, storage, and processor usage. This includes knowing how to inspect and manage the system and user processes running in the background. This chapter will outline some tools and utilities that can be used to monitor … Read more
• Adding and Managing AlmaLinux 9 Swap Space
  An essential part of maintaining the performance of an AlmaLinux 9 system involves ensuring that adequate swap space is available comparable to the memory demands placed on the system. Therefore, this chapter provides an overview of swap management on AlmaLinux 9. What is Swap Space? Computer systems have a finite amount of physical memory available … Read more
• Adding a New Disk to an AlmaLinux Volume Group and Logical Volume
  In the previous chapter, we looked at adding a new disk drive to an AlmaLinux 9 system, creating a partition and file system, and then mounting that file system to access the disk. An alternative to creating fixed partitions and file systems is to use Logical Volume Management (LVM) to create logical disks comprising space … Read more
• Adding a New Disk Drive to an AlmaLinux 9 System
  One of the first problems users and system administrators encounter is that systems need more disk space to store data. Fortunately, disk space is now one of the cheapest IT commodities. In this and the next chapter, we will look at configuring AlmaLinux 9 to use the space provided when a new physical or virtual … Read more
• Configuring an AlmaLinux 9 Postfix Email Server
  Along with acting as a web server, email is one of the primary uses of an AlmaLinux 9 system, particularly in business environments. Given the importance and popularity of email, it is surprising to some people to find out how complex the email structure is on a Linux system. This complexity can often be overwhelming … Read more
• Setting Up an AlmaLinux Web Server
  The Apache web server is among the many packages that make up the AlmaLinux 9 operating system. The scalability and resilience of AlmaLinux 9 make it an ideal platform for hosting even the most heavily trafficked websites. This chapter will explain how to configure an AlmaLinux 9 system using Apache to act as a web … Read more
• An AlmaLinux 9 Container Tutorial
  Now that the basics of Linux Containers have been covered in the previous chapter, this chapter will demonstrate how to create and manage containers using the Podman, Skopeo, and Buildah tools on AlmaLinux 9. By the end of this chapter, you will have a clearer understanding of how to create and manage containers on AlmaLinux … Read more
• An Introduction to AlmaLinux 9 Containers
  The preceding chapters covered the concept of virtualization, emphasizing creating and managing virtual machines using KVM. This chapter will introduce a related technology in the form of Linux Containers. While there are some similarities between virtual machines and containers, key differences will be outlined in this chapter, along with an introduction to the concepts and … Read more
• Managing KVM on AlmaLinux 9 using the virsh Command-Line Tool
  In previous chapters, we have covered the installation and configuration of KVM-based guest operating systems on AlmaLinux 9. This chapter explores additional areas of the virsh tool that have not been covered in previous chapters and how it may be used to manage KVM-based guest operating systems from the command line. The virsh Shell and … Read more
• Creating an AlmaLinux 9 KVM Networked Bridge Interface
  By default, the KVM virtualization environment on AlmaLinux 9 creates a virtual network to which virtual machines may connect. It is also possible to configure a direct connection using a MacVTap driver. However, as outlined in the chapter entitled “An Overview of Virtualization Techniques”, this approach does not allow the host and guest systems to … Read more
• Creating KVM Virtual Machines on AlmaLinux 9 with virt-install and virsh
  In the previous chapters, we explored the creation of KVM guest operating systems on an AlmaLinux 9 host using Cockpit and the virt-manager graphical tool. This chapter will focus on creating KVM-based virtual machines using the virt-install and virsh command-line tools. These tools provide all the capabilities of the virt-manager and Cockpit options with the … Read more
• Creating KVM Virtual Machines on AlmaLinux 9 using virt-manager
  The previous chapter explored how to create KVM virtual machines on AlmaLinux 9 using the Cockpit web tool. With the caveat that virt-manager may one day be discontinued once the Virtual Machines Cockpit extension is fully implemented, this chapter will cover using this tool to create new virtual machines. Starting the Virtual Machine Manager If … Read more
• Creating KVM Virtual Machines on AlmaLinux 9 using Cockpit
  KVM-based virtual machines can easily be configured on AlmaLinux 9 using the virt-install command-line tool, the virt-manager GUI tool, or the Virtual Machines module of the Cockpit web console. This chapter will use Cockpit to install an operating system as a KVM guest on an AlmaLinux 9 host. The chapter titled “Creating KVM Virtual Machines … Read more
• Installing KVM Virtualization on AlmaLinux
  Earlier versions of Red Hat Enterprise Linux (on which AlmaLinux is based) provided two virtualization platforms: Kernel-based Virtual Machine (KVM) and Xen. In recent releases, support for Xen has been removed, leaving KVM as the only bundled virtualization option supplied with AlmaLinux 9. In addition to KVM, third-party solutions are available in products such as … Read more
• Sharing Files between AlmaLinux 9 and Windows with Samba
  Although Linux has made some inroads into the desktop market, its origins and future are very much server-based. It is unsurprising, therefore, that AlmaLinux 9 can act as a file server. It is also common for AlmaLinux and Windows systems to be used side by side in networked environments. Therefore, it is a common requirement … Read more
• Using NFS on AlmaLinux 9 to Share Files with Remote Systems
  AlmaLinux 9 provides two mechanisms for sharing files and folders with other systems on a network. One approach is to use a technology called Samba. Samba is based on Microsoft Windows Folder Sharing and allows Linux systems to make folders accessible to Windows systems and access Windows-based folder shares from Linux. This approach can also … Read more
• Displaying AlmaLinux 9 Applications Remotely (X11 Forwarding)
  In the previous chapter, we looked at how to display the entire AlmaLinux 9 desktop on a remote computer. While this works well if you need to display the entire desktop remotely, it could be considered overkill if you only want to display a single application. Therefore, this chapter will look at displaying individual applications … Read more
• AlmaLinux 9 Remote Desktop Access with VNC
  AlmaLinux 9 can be configured to provide remote access to the graphical desktop environment over a network or internet connection. Although not enabled by default, displaying and accessing an AlmaLinux 9 desktop from a system anywhere else on a network or the internet is relatively straightforward. This can be achieved regardless of whether that system … Read more
• Configuring SSH Key-based Authentication on AlmaLinux 9
  When an AlmaLinux 9 system is first installed, it is configured by default to allow remote command-line access via Secure Shell (SSH) connections. SSH provides password-protected and encrypted access to the system for the root account and any other users added during the installation phase. However, this level of security is inadequate and should be … Read more
• AlmaLinux 9 Firewall Configuration with firewalld
  A firewall is vital in protecting a computer system or network of computers from external attacks (typically from an external source via an internet connection). For example, any computer connected directly to an internet connection must run a firewall to protect against malicious activity. Similarly, any internal network must have some form of firewall between … Read more