×

This article covers how to use the iostat command in Linux. In fact, iostat command is used to monitor CPU utilization and I/O (input /output) statistics of all the disks and file systems. nfsiostat command is used to monitor i/o statistics of network file system(NFS).


iostat command generally generates two reports:

  • CPU utilization report.
  • All disks i/o statistics report.


To generate the reports, iostat command reads some of the system files . These files are:

  • /proc/diskstats for disk stats.
  • /proc/stat for system stats.
  • /sys for block device stats.
  • /proc/devices for persistent device names.
  • /proc/self/mountstats for all  the network filesystems.
  • /proc/uptime for information regarding system uptime.


This article covers the different methods to check if the disk is HDD or SSD in a Linux operating system like Ubuntu 20.04 LTS server. In fact, Checking SSD/HDD health in Linux will help you to identify failed drives and they can be replaced before any data loss occurs. Therefore, If you are a system administrator and responsible for managing Linux systems in Datacenter, then, it is recommended to check the health of the SSD and HDD drives regularly. 

Checking SSD/HDD health in Linux will help you to identify failed drives and they can be replaced before any data loss occurs. 


How to use SMART monitoring tools in Linux ?

Smart monitoring tools is a control and monitoring utility for SATA, SCSI hard drives and solid state drive. The tool comes with a command called 'smartctl'.

Use yum to check which package provides smartctl command:

# yum provides smartctl

The output will suggest that smartmontools is the package that distributes smartctl command.

To Install smartmontools, run:

# yum install smartmontools

Use smartctl command:

# smartctl -a /dev/sda


This article covers the complete procedure of Installing VMware Workstation on Linux Mint 20.1 Ulyssa. In fact, VMware is a mature and stable virtualization solution that allows you to run multiple, isolated operating systems on a single machine. This enables one to have Virtual machines of different operating systems running off the host resources. 

The VMware Tools offer several useful functionalities such as faster graphics performance, shared folders, shared clipboards, drag and drop operations, and more.


This article covers the differences between Docker containers, LXD, and LXC. In fact, You can use any of these containers as per your working environment and the requirements as each container technology has its own advantage and the limitations. 


This article covers how to create and manage guest virtual machines on KVM from the command-line. In fact, KVM (Kernel based Virtual Machine) is an opensource virtualization technology built for Linux machines. It comprises a kernel module – kvm.ko which provides the core virtualization platform and a processor-specific module ( kvm-intel.ko for Intel processors or kvm-amd.ko for AMD processors ).


How to Install KVM, Qemu, virt-manager & libvirtd daemon ?

To install KVM and associated packages, run the below command:

$ sudo apt install -y qemu qemu-kvm libvirt-daemon libvirt-clients bridge-utils virt-manager

The command installs the following packages:

  • qemu-kvm –  This is the main KVM package that provides virtualization support.
  • libvirt – Includes the libvirtd daemon which supports creation and management of virtual machines.
  • libvirt-client – This package provides the virsh utility used for interacting with virtual machines.
  • virt-install – A utility that helps you to create virtual machines and install OS on those virtual machines from command line.
  • virt-viewer – A utility that displays the graphical view for the virtual machine.

Once installed, we need to confirm if the required kvm modules are loaded. Therefore, run the command:

$ lsmod | grep kvm

Additionally, confirm that the libvirtd daemon is running as follows:

$ sudo systemctl status libvirtd.service


This article covers how to use the divmod() function in Python. In fact, Python divmod() function is employed to return a tuple that contains the value of the quotient and therefore the remainder when dividend is divided by the divisor. It takes two parameters where the first one is the dividend and the second one is the divisor.


Python divmod() function Parameter Values:

  • divident - This parameter contains the number you want to divide.
  • divisor - This parameter contains the number you want to divide with.


This article covers the installation of KVM on Rocky Linux / AlmaLinux. In fact, Kernel-Based Virtual Machine (KVM) is an open-source Linux-based hypervisor that is inbuilt within the Linux Linux Operating systems. Is grouped as a type 1 hypervisor as it possesses type 1 characteristics such as direct access to hardware with VM's. It has kvm.ko kernel module which creates a core virtualization infrastructure and supports both Intel and AMD processors.


This article covers the different ways to install Node.js in your Ubuntu system. Node.js is a popular back-end JavaScript runtime used for creating web servers and scalable network apps. The environment supports server-side scripting - producing dynamic content for web pages before they are served to the user.

NPM is a package manager for JavaScript and the default package manager for Node.js. As such, NPM is installed alongside Node.js as a recommended feature.


This article covers how to use the free command with some examples. In fact, the free command provides information about unused and used memory and swap space on any computer running Linux or another Unix-like operating system.

For more information about free command type in your terminal:

$ man free


This article covers the basic nvm commands that you can use to install and manage multiple versions of Node.JS. In fact, Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.


You can use the following command to list installed version's of Node for the current user:

$ nvm ls 

With this command you can find available Node.js version for the installation:

$ nvm ls-remote 

To find the default Node version set for the current user, run the command:

$ nvm run default --version 


This article covers how to use the vmstat command in Linux. In fact, vmstat command in Linux/Unix is a performance monitoring command of the system as it gives the information about processes, memory, paging, block IO, disk, and CPU scheduling. All these functionalities makes the command vmstat also known as virtual memory statistic reporter.


This article covers how you can install Kubectl on your Linux system and use it to operate your Kubernetes clusters if you are fond of using the command-line interfaces. Infact, Kubectl tool is very efficient in terms of cluster management and application deployment. 

Kubectl is a command-line tool for Kubernetes. It allows us to execute Kubernetes operations via the API. We can use Kubectl to deploy apps, check logs as well as manage all the other resources of the cluster.

Kubernetes uses an HTTP-based REST API which is the actual Kubernetes user interface employed to manage it. This means that every Kubernetes operation is represented as an API endpoint and can be carried out based on an HTTP-request sent to the endpoint. 


This article covers the Installation process of NodeJS on Rocky Linux. Nodejs is a JavaScript runtime built on Chrome's V8 JavaScript engine and is designed to build scalable network applications.


This article covers how to install Minikube on your Ubuntu 20.04 machine. Minikube is an open source tool that allows you to set up a single-node Kubernetes cluster on your local machine. The cluster is run inside a virtual machine and includes Docker, allowing you to run containers inside the node. 

Now, you can use the single-node Kubernetes with minikube to learn one of the most famous containers orchestration tools in the Cloud Native era. 


To enable and access kubernetes dashboard , run the command:

$ minikube dashboard

This will open the Kubernetes dashboard in the web browser.


To stop the minikube, run:

$ minikube stop

To delete the minikube, run:

$ minikube delete

To Start the minikube, run:

$ minikube start


This article covers how to install nodejs and npm on your Debian system with different methods. Also, you will learn how to uninstall npm from your Debian system. Node.js is a JavaScript platform for general-purpose programming that allows users to build asynchronous network applications quickly. By leveraging JavaScript on both the front and backend, Node.js can make web application development more consistent and integrated.


To Install the Official Debian Node.js Package:

1. To get Node.js from the default Debian software repository, you can use the apt package manager. First, refresh your local package index:

$ sudo apt update

2. Then install the Node.js package, and npm the Node Package Manager:

$ sudo apt install nodejs npm

3. To verify that the install was successful, run the node command with the -v flag to get the version:

$ node -v


To Remove Node.js:

1. To remove either of these versions, type the following:

$ sudo apt remove nodejs

2. To uninstall a version of Node.js that you have enabled using nvm, first determine whether or not the version you would like to remove is the current active version:

$ nvm current

3. If the version you are targeting is not the current active version, you can run:

$ nvm uninstall node_version

This command will uninstall the selected version of Node.js.

4. If the version you would like to remove is the current active version, you must first deactivate nvm to enable your changes:

$ nvm deactivate


This article covers how to install Virt-Viewer on a Linux Mint 20 system. virt-viewer is a minimal tool for displaying the graphical console of a virtual machine. The console is accessed using the VNC or SPICE protocol. The viewer can connect to remote hosts to lookup the console information and then also connect to the remote console using the same network transport.


Functions of Virt Viewer: 

  • Connect to KVM virtual machines remotely via the SPICE remote desktop protocol.
  • Automatically adjust display resolution of the KVM virtual machines.
  • Use multiple monitors for the KVM virtual machines.
  • Passthrough USB devices from your computer to the KVM virtual machines.
  • Share folders from your computer to the KVM virtual machines.


To install Virt Viewer on Linux:

1. First, update the APT package repository cache with the following command:

$ sudo apt update

2. To install Virt Viewer on Ubuntu 20.04 LTS, run the following command:

$ sudo apt install virt-viewer --no-install-recommends --no-install-suggests

Then, confirm the installation, press Y and then press <Enter>.


This article covers the top-performing virtualization software specifically for Linux. Virtualization is the act of creating a "virtual machine" (VM) for every layer and system excerpted from the original, whether it is storage, hardware, computer network resources, or the operating system as a whole.

Virtualization is the process of developing virtual versions of operating systems, hardware platforms, storage devices, or computer network resources.

Basically, Some of the discussed virtualization paradigms are cross-platform such as XenProject, VirtualBox, and Microsoft Hyper-V, but Linux KVM and oVirt are specifically designed and created for the Linux operating systems.


A key advantage of running a virtual machine is that it allows you to run apps that would otherwise not be available due to having very different system requirements, which is one particular reason why virtualization has become so important in business.


The Top 5 Open Source Virtualization Software includes:

  • Xen Project.
  • VirtualBox.
  • KVM.
  • oVirt.
  • ProxMox.


This article covers how to clear the cache and buffer memory of the physical memory along with clearing the swap space when needed.

Every Linux System has three options to clear cache without interrupting any processes or services.


If you want to clear Swap space, you may like to run the below command.

$ swapoff -a && swapon -a


To Clear PageCache, dentries and inodes:

$ sync; echo 3 > /proc/sys/vm/drop_caches


To Clear PageCache only:

$ sync; echo 1 > /proc/sys/vm/drop_caches


To Clear dentries and inodes:

$ sync; echo 2 > /proc/sys/vm/drop_caches


This article covers the different methods to perform the installation of NodeJS on the CentOS 8 system.

Now that NodeJS is installed on your CentOS 8 system, you can use it to deploy a NodeJS application on the system.
Node.js is a cross-platform, runtime environment that was built on Chrome's JavaScript. This environment is designed to execute JavaScript code on the server-side.

To check Node version number, run the command:

# node --version


This article covers how to install and use the Docker-compose on CentOS 8 system. By using the Docker-compose, you can deploy multiple Docker applications with container services through a single command. 

Basically, Docker Compose is a tool that can be used to define and run multiple containers as a single service. With Docker Compose, you can link multiple containers and deploy an application from a single command. 

It is mainly used in the development, testing and staging environment. 

Docker Compose uses a YAML file to define a complex stack in a file and running it with a single command.


To install Docker on CentOS:

1. Before starting, make sure you have Docker installed on your server. If not installed, you will need to add Docker-CE repository to your system. 

You can add it with the following command:

$ dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo

2. Once the repository is added, install the latest version of docker using the following command:

# dnf install docker-ce --nobest -y
# systemctl start docker
# systemctl enable docker

3. You can verify the docker version with the following command:

$ docker --version


This article covers how to install VMware Workstation on your instance of Ubuntu 20.04. With a virtual machine application like VMware, you can run another operating system inside your current operating system.


To Install VMware in Ubuntu:

1. Install required build packages

Open a terminal (Ctrl+Alt+T) and use the command below to install required build packages and Linux Kernel headers:

$ sudo apt install build-essential

2. Download VMware Workstation Player

Next step is to download the VMware Workstation Player from their website.

https://www.vmware.com/products/workstation-player.html

3. Install VMware Player

4. Use the command below to make the file executable:

$ chmod +x ~/Downloads/VMware-Player*

5. And then run the installation file:

$ sudo ~/Downloads/VMware-Player*

This will open an installation window.


To Uninstall VMware Player from Ubuntu:

If, for some reasons, you want to uninstall VMware Player, use the following command:

$ sudo /usr/bin/vmware-installer -u vmware-player

Press "Enter" and VMware Player will be removed from your system.


This article covers how to install Yarn on Ubuntu 20.04 LTS system. Yarn is a JavaScript package manager compatible with npm that helps you automate the process of installing, updating, configuring, and removing npm packages. 

It caches every download package and speeds up the installation process by parallelizing operations.


To Yarn on Ubuntu Linux:

1. Import the repository’s GPG key and add the Yarn APT repository to your system by running the following commands:

$ curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
$ echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list

2. Once the repository is enabled, update the package list, and install Yarn:

$ sudo apt update
$ sudo apt install yarn

3. If you installed Node trough nvm, skip the Node.js installation with:

$ sudo apt install --no-install-recommends yarn

4. Once completed, verify the installation by printing the Yarn version:

$ yarn --version


This article will guide you through the processes of Installing VirtualBox, CentOS 8 as a Virtual Machine (VM) on VirtualBox.



More Linux Tutorials

We create Linux HowTos and Tutorials for Sys Admins. Visit us on IbmiMedia.com

Also for Tech related tips, Visit forum.outsourcepath.com or General Technical tips on www.outsourcepath.com