Virtualization 101

What is virtualization?

The idea of virtualization is to to be able to run virtual computers on existing piece of physical machine. One computer will get one IP address, with virtualization I can have multiple IPs on same hardware.

I first knew of virtualization while working on software for banks. The "IT department" of bank would create a VM for me to install software :)

https://www.redhat.com/en/topics/virtualization/what-is-virtualization

Setting up VM

Install VirtualBox which is a full virtualizer https://www.virtualbox.org/wiki/Downloads

Then download the ISO for OS you want to have a VM for and attach it to VirtualBox storage as shown in screenshot below(In MacOS). Ubuntu ISO can be downloaded from here, https://www.ubuntu.com/download/desktop

http://askubuntu.com/questions/825437/ubuntu-16-in-vm-does-not-have-access-to-internet

Regarding the Network setup, it really depends on the nature of the network being used. In following example, in one case wireless works for me.

while in wired environment ethernet adaptor works.

Resizing the VM
In case you need to increase the VM RAM or Disk size, after you created your VM, then follow the process as below :

STEP 1 : shut down VM

STEP 2 : resize the VM vdi using host terminal (windows in mycase)
VBoxManage modifyhd "C:\Users\AS18\VirtualBox VMs\WM_Bridge\WM_Bridge.vdi" --resize 100000

STEP 3 : 
Then, using gparted resize the /dev/sda1

Original config

Delete linux-swap

Reassign the size to linux-swap

http://askubuntu.com/a/558215/37643

http://askubuntu.com/a/95026/37643

Share folder
---------------------

1) Install guest edition

followed by sudo /media/prayagupd/VBOXADDITIONS_5.1.8_111374/VBoxLinuxAdditions.run and then reboot.

How to Access Folders on Your Host Machine from an Ubuntu Virtual Machine in VirtualBox

2) add current guest user to the vboxsf usergroup

sudo adduser $USER vboxsf
[sudo] password for prayagupd:
Adding user `prayagupd' to group `vboxsf' ...
Adding user prayagupd to group vboxsf
Done.

verify that its working, 

id $USER

uid=1000(prayagupd) gid=1000(prayagupd) groups=1000(prayagupd),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),113(lpadmin),128(sambashare),999(vboxsf)

3) mount shared folder

Create a mount folder on host machine with Auto-mount Yes, and Access Full.