Make a VM and build your custom OS¶

Initialize a virtual machine virtual1.

$ mkdir Teefaa && cd Teefaa
$ teefaa init virtual1

2. It will take a while to complete the initial setting, and the following files are created.

$ tree -a -L 2
.
├── .teefaa
│   ├── ssh_config_virtual1          --- ssh config
│   ├── ssh_key                 --- ssh private key
│   ├── ssh_key.pub             --- ssh public key
│   └── teefaa-debian-live.iso  --- Teefaa LiveCD image
└── virtual1
    ├── Teefaafile.yml          --- teefaa config
    ├── .vagrant                --- vagrant dot directory
    └── Vagrantfile             --- vagrant config
Note

What teefaa init actually does is;

Make configuration files and ssh key pair.

Make a VM with using Vagrant and VirtualBox.

Download Debian LiveCD to the VM and build Teefaa LiveCD.

Take a look at virtual1/Teefaafile.yml. You can find that Teefaa provisions CentOS 6 basic image as default.

Change directory to virtual1 and provision the basic CentOS 6 image.
```
$ cd virtual1
$ teefaa provision
```
Note
- What teefaa provision does is;
  Download CentOS 6 image if it doesn’t exist on local.
  
  Boot virtual1 with the Teefaa LiveCD.
  
  Install CentOS 6 on virtual1 over ssh.
  
  Reboot virtual1 with local disk.
Make some changes and make a snapshot of the system.
```
$ teefaa ssh
[teefaa@virtual1 ~]$ sudo yum install screen
[teefaa@virtual1 ~]$ echo Hello World! > test.txt
[teefaa@virtual1 ~]$ exit
$ teefaa make-snapshot
```
Note
- What make-snapshot does is;
  Copy all files into a temporal directory.
  
  Compress it with SquashFS.
  
  Download and save it in .teefaa directory.