Small talk on Vagrant

Intro:

Vagrant is a tool for building and managing virtual machine environments.
A modular framework to work with virtual machines.

Why to use Vagrant :

- No need to learn different CLI command of Virtualization providers , vagrant takes cares to manage the underlying VM's with its easy CLI interface. Commands are like,

vagrant up

vagrant ssh

- Well defined environments as configuration used to create the environments is in simple text files. User can recreate as many Vagrant Instances (VMs) using same Vagrant file .

- Vagrant is capable of executing configuration management software like Puppet/Ansible/Chef once the base system is ready (using box). This help o setup the environment (System + Application) on the target machines in automated way.

- Developer can create/destroy multiple development environments in minutes.

- As vagrant is wrapper only , you can choose the guest OS images supported by the virtualization platform you choice. Example on CentOS 8, you may run CentOS 7 VM.

The most important concepts of vagrant are,

providers
provisioners

Providers

Who provides virtualization support
They magic VMs into existence
It falls into two category Local or Remote

Local providers are VirtualBox, VMWare, Docker
Remote providers are AWS, Openstack

Provisioners

Provision the VMs
They shared, repeatable configurations of VMs
Some provisioners are SHELL, ansible.

Steps to use Vagrant:

1] Initiate vagrant to get vagrant file.

$vagrant init -m <image-name>

2] After initialising vagrant, you will get a vagrant file. We have to update vagrant file with the configurations.

cat vagrantfile

3] Then, we have to up the vagrant. This will bring up the instance.

vagrant up

4] Later we have to ssh to the instance using "vagrant ssh" command.
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