Linux Assignment Part – 1

What is EPEL and Write a instructions to install and use it.

The Extra Packages for Enterprise Linux (EPEL) is a repository of additional software packages that are built for the Red Hat Enterprise Linux (RHEL) and CentOS operating systems. The packages in the EPEL repository are not part of the core RHEL or CentOS distributions, but they are built to be compatible with these systems and are maintained by a community of volunteers.

To install and use EPEL, you can follow these steps:

• Enable the EPEL repository on your system. This can be done by installing the epel-release package. On CentOS, you can use the following command:

sudo yum install epel-release

• On RHEL, you will need to enable the EPEL repository by creating a file at /etc/yum.repos.d/epel.repo with the following content:

[epel]
name=Extra Packages for Enterprise Linux $releasever - $basearch
baseurl=https://download.fedoraproject.org/pub/epel/$releasever/$basearch
enabled=1
gpgcheck=1
gpgkey=https://download.fedoraproject.org/pub/epel/RPM-GPG-KEY-EPEL-$releasever

• Once the EPEL repository is enabled, you can install packages from it using the yum package manager. For example, to install the htop package from the EPEL repository, you can use the following command:

sudo yum install htop

• To update a package from the EPEL repository, you can use the yum update command. For example, to update the htop package, you can use the following command:

sudo yum update htop

• To remove a package from the EPEL repository, you can use the yum remove command. For example, to remove the htop package, you can use the following command:

sudo yum remove htop

• By default, the EPEL repository is enabled on CentOS systems, but it is not enabled on RHEL systems. You will need to enable the repository and install the epel-release package on RHEL systems in order to use the EPEL repository.

What is difference between hypervisor and cloud?

A hypervisor, also known as a virtual machine manager (VMM), is software that allows multiple operating systems to run on a single physical host machine. A hypervisor creates virtual machines (VMs) on the host and assigns each VM its own virtualized hardware resources, such as CPU, memory, and storage.

Cloud computing, on the other hand, is a model for delivering computing resources, such as servers, storage, and networking, over the internet. Cloud computing providers, such as Amazon Web Services (AWS), Microsoft Azure, and Google Cloud, offer a variety of services that allow users to rent computing resources on demand, without the need to purchase and maintain physical hardware.

One key difference between hypervisors and cloud computing is the level of control that users have over the underlying hardware. With a hypervisor, users have control over the hardware on which their VMs are running, and they can install and configure the hypervisor and VMs as they see fit. In the cloud, users do not have direct control over the physical hardware, but they can choose from a variety of services and configurations offered by the cloud provider.

What are the Network Adaptor(Driver) you have in VirtualBox and write a use case of it?

VirtualBox, a virtualization software developed by Oracle, provides a number of network adapter options that can be used to connect virtual machines (VMs) to networks. The available network adapters include:

NAT: The NAT (Network Address Translation) adapter allows the VM to connect to the internet and other networked resources through the host machine's network connection. This adapter is useful for VMs that need internet access, but do not need to be directly accessible from other machines on the network.

Bridged: The Bridged adapter allows the VM to connect directly to the host machine's network and be treated as a separate device on the network. This adapter is useful for VMs that need to be accessible from other machines on the network or that need to communicate with other devices on the same network.

Host-only: The Host-only adapter allows the VM to communicate with the host machine and other VMs on the same host-only network, but it does not provide internet access or allow communication with other devices on the host machine's network. This adapter is useful for creating a private network between VMs and the host machine.

Internal: The Internal adapter allows the VM to communicate with other VMs on the same host machine, but it does not provide internet access or allow communication with other devices on the host machine's network. This adapter is useful for creating a private network between VMs on the same host machine.

Generic: The Generic adapter allows the VM to use a custom driver or filter to connect to a network. This adapter is useful for advanced network configurations or for connecting to networks that are not supported by the other adapter types.

Here is an example use case for each of these network adapter types:

NAT: A developer uses a VM with a NAT adapter to test a web application that needs internet access. The developer can access the internet through the host machine's network connection, but the VM is not directly accessible from other machines on the network.

Bridged: A network administrator uses a VM with a Bridged adapter to simulate a separate device on the network. The VM can communicate with other devices on the network and can be accessed remotely by other machines.

Host-only: A security researcher uses a VM with a Host-only adapter to create a private network for testing and experimentation. The VM can communicate with the host machine and other VMs on the same host-only network, but it cannot access the internet or communicate with other devices on the host machine's network.

Internal: A team of developers uses VMs with Internal adapters to create a private network for testing and collaboration. The VMs can communicate with each other, but they do not have internet access and are not accessible from other devices on the host machine's network.

Generic: An engineer uses a VM with a Generic adapter to connect to a custom network that is not supported by the other adapter types. The engineer can use a custom driver or filter to connect the VM to the network and communicate with other devices on the network.