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Recent Posts

• Creating KVM Virtual Machines on CentOS Stream 9 using Cockpit
  KVM-based virtual machines can easily be configured on CentOS Stream 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 a CentOS 9 host. The chapter titled “Creating KVM Virtual … Continue reading “Creating KVM Virtual Machines on CentOS Stream 9 using Cockpit”
• Installing KVM Virtualization on CentOS Stream 9
  Earlier versions of CentOS 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 CentOS Stream 9. In addition to KVM, third-party solutions are available in products such as VMware and Oracle VirtualBox. Since KVM is … Continue reading “Installing KVM Virtualization on CentOS Stream 9”
• An Overview of CentOS Stream 9 Virtualization Techniques
  Virtualization is the ability to run multiple operating systems simultaneously on a single computer system. While not necessarily a new concept, Virtualization has come to prominence in recent years because it provides a way to fully utilize the CPU and resource capacity of a server system while providing stability (in that if one virtualized guest … Continue reading “An Overview of CentOS Stream 9 Virtualization Techniques”
• Sharing Files between CentOS Stream 9 and Windows Systems 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 CentOS Stream 9 can act as a file server. It is also common for CentOS 9 and Windows systems to be used side by side in networked environments. Therefore, it is … Continue reading “Sharing Files between CentOS Stream 9 and Windows Systems with Samba”
• Using NFS on CentOS Stream 9 to Share Files with Remote Systems
  CentOS Stream 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 … Continue reading “Using NFS on CentOS Stream 9 to Share Files with Remote Systems”
• Displaying CentOS Stream 9 Applications Remotely (X11 Forwarding)
  In the previous chapter, we looked at how to display the entire CentOS Stream 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 … Continue reading “Displaying CentOS Stream 9 Applications Remotely (X11 Forwarding)”
• CentOS Stream 9 Remote Desktop Access with VNC
  CentOS Stream 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 a CentOS 9 desktop from a system anywhere else on a network or the internet is relatively straightforward. This can be achieved regardless of whether that … Continue reading “CentOS Stream 9 Remote Desktop Access with VNC”
• Configuring SSH Key-based Authentication on CentOS Stream 9
  When a CentOS Stream 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 … Continue reading “Configuring SSH Key-based Authentication on CentOS Stream 9”
• CentOS Stream 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 … Continue reading “CentOS Stream 9 Firewall Configuration with firewalld”
• CentOS Stream 9 Firewall Basics
  A firewall is a vital component in protecting an individual computer system or network of computers from external attacks (typically from an internet connection). Any computer connected directly to an internet connection should ideally run a firewall to protect against malicious activity. Similarly, any internal network must have some form of firewall between it and … Continue reading “CentOS Stream 9 Firewall Basics”
• CentOS Stream 9 Network Management
  It is difficult to envisage a CentOS Stream 9 system that does not have at least one network connection, and harder still to imagine how such an isolated system could be of much practical use. However, the simple fact is that CentOS 9 is designed to provide enterprise-level services over network and internet connections. Therefore, … Continue reading “CentOS Stream 9 Network Management”
• Managing CentOS Stream 9 systemd Units
  To gain proficiency in CentOS Stream 9 system administration, it is essential to understand the concepts of systemd units with a particular emphasis on two specific types known as targets and services. This chapter aims to provide a basic overview of the different systemd units supported by CentOS Stream 9 combined with an overview of … Continue reading “Managing CentOS Stream 9 systemd Units”
• CentOS Stream 9 Software Installation and AppStreams
  It is doubtful that a newly installed CentOS Stream 9 system will contain all the software packages to perform the tasks for which it is intended. Even once all the required software has been installed, it is almost certain that newer versions of many of those packages will be released during the system’s lifespan. In … Continue reading “CentOS Stream 9 Software Installation and AppStreams”
• Managing CentOS Stream 9 Users and Groups
  During the installation of CentOS Stream 9, the installer created a root or superuser account and required that a password be configured. The installer also provided the opportunity to create a user account for the system. We should remember that CentOS 9 is an enterprise-class, multiuser, and multi-tasking operating system. To use the full power … Continue reading “Managing CentOS Stream 9 Users and Groups”
• Using Cockpit on CentOS Stream 9
  Although equipped with the latest Linux desktop environment, CentOS Stream 9 is very much a server operating system. As such, most CentOS 9 deployments will be to remote physical servers or as cloud-based virtual machine instances. Invariably, these systems run without a keyboard, mouse, or monitor, with direct access only available via the command prompt … Continue reading “Using Cockpit on CentOS Stream 9”
• Allocating Windows Disk Partitions to CentOS Stream 9
  In the previous chapter, we looked at installing CentOS 9 on the same disk as Windows. This so-called “dual boot” configuration allows the user to have both operating systems installed on a single disk drive with the option to boot one or the other when the system is powered on. This chapter is intended for … Continue reading “Allocating Windows Disk Partitions to CentOS Stream 9”
• Dual Booting CentOS Stream 9 with Windows
  Like most Linux distributions, CentOS Strea 9 will happily co-exist on a hard disk drive with just about any version of Windows up to and including Windows 11. This is a concept known as dual-booting. When you power up the system, you will see a menu providing the option to boot either your CentOS 9 … Continue reading “Dual Booting CentOS Stream 9 with Windows”
• Installing CentOS Stream 9 on a Clean Disk Drive
  There are now two ways in which a CentOS Stream 9 system can be deployed. One method is to either purchase new hardware or re-purpose an existing computer system on which to install and run the operating system. Another option is to create a cloud-based operating system instance using services such as Amazon AWS, Google … Continue reading “Installing CentOS Stream 9 on a Clean Disk Drive”
• Rocky Linux 9 System and Process Monitoring
  An essential part of running and administering a Rocky Linux 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 … Continue reading “Rocky Linux 9 System and Process Monitoring”
• Adding and Managing Rocky Linux 9 Swap Space
  An essential part of maintaining the performance of a Rocky Linux 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 Rocky 9. What is Swap Space? Computer systems have a finite amount of physical memory … Continue reading “Adding and Managing Rocky Linux 9 Swap Space”