Setup CentOS 7 VM on VirtualBox

This is step by step guide which will let you run the CentOS 7 VM on your virtual box installation. In this tutorials are illustrated using Mac.

Installing VirtualBox

VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use




Installing Vagrant

Vagrant manages virtual machines hosted in Oracle VirtualBox. A virtual machine is a software implementation of a computer, running a complete operating system stack on a virtualizer.

  • Download Vagrant from here. Install the vagrant.
  • Check the installation by running below command.

Setup CentOS VM

Once you are done with vagrant, now you are ready to setup your CentOS VM. 
Run below command, which will create "vagrantfile" under the current working directory. The vagrantfile can be used to configure and provision the VM.


Once you see above message you can run "vagrant up" command, which will pull the CentOS image and create a VM under virtual box, as shown in below image.


Connecting to VM

Once the CentOS is up successfully, you can check in the VirtualBox its setting as well as you can change those.

If CentOS is running then you can connect VM via ssh using below command.


Now your CentOS VM is ready to use.

You can take a snapshot of VM before use, so it can be discarded anytime and clean VM will be ready to use. You can also delete the VM using Virtualbox as well. 

Nice little changes in iOS 11

Yesterday Sept 19 2017 Apple released iOS 11. iOS 11 is bundled with lots of features, which you might be aware right now, but there are more little changes. 

  • First striking change you will notice once you get started after upgrading to iOS 11 is the icons. The icons of iOS pre-loaded apps would feel different, and would give you feel of having a new device in hand. 
  • The calculator app UI is redesigned as shown below 

  • If you take a screenshot, iOS 11 will let you edit the screenshot before saving.


  • One thing I noticed that the margin left for the header part is more in majority of the apps like settings, photos. I am not sure this thing is with iPhone 5s only or with others as well, but certainly it eats up screen real estate.



I would keep updating this list as and when I encounter new ones.

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