Education: Getting Started with dEWDrop VM

This is a quick tour of the environment in the dEWDrop Virtual Machine intended to familiarize you with it, and take advantage of a few of its many resources.

The dEWDrop Virtual Machine was kindly built and distributed by David Wicksell. It includes work from many members of the community. Many thanks to all of them for sharing their work so generously.


The VM can be downloaded from:               
http://www.fourthwatchsoftware.com/


 

Hands-on Session

 

 
 
  • Import the VM
  • Take a snapshot of it, fresh as imported. This is the equivalent of a backup to which you can return later. 
    Seriously, take this snapshot ! you will need it.
Snapshot 1
Snapshot 2
  • Setup the network in Virtual Box: do this by going to the settings menu, 

    Settings menu 1
     
  • Selecting Network, and then in "attached to" replacing the option  "NAT" with "Bridge".
    • In the NAT option, the VM guest gets access to the network through your host, but it doesn't get an IP number that is visible in the local network. 
    • In the Bridge option, the VM guest gets an IP number assigned and it becomes visible in the local network outside of your host.  
    • Make sure to select in the option "Name" the actual network device that your host is using to connect to the network (if you are in a laptop, it is important to differentiate between the wireless and the wired adapter).
    • In the "Promiscuous Mode" option, select "Allow All" (this is not the safest option, but it is the one that will make your exercise easier).

      VirtualBox network setup Bridge
 
  • Start the VM

    Start menu button 1
     
  • Notice that this is a text-based VM so all your interactions will be in the command line.

    Login screen
     
  • Login with username : vista,   password : ewd
  • As soon as you log in, you will see text describing some of the credentials that you will need for the exercises.
    Write down that information.
    More explicitly

    Access code:     worldvista6
    Verify code:      $#happy7
    DUZ                   77

    Screen after login

     
  • Look at the IP number of the Virtual Machine.

    Use the command:

    ifconfig


    Checking IP number in VM

    Write down the IP number.
    We will use it MANY times in this exercise.

    BTW, for the rest of this exercise in this text you will see the IP number 192.168.200.107, which happens to be the IP number that I got when preparing this instructions. As you go through this exercise, you must replace this IP number with the one that you get when running the ifconfig command above.
     
  • Visit the key directories.
    Do:

    pwd
    ls
    ls   -l
    cd /home/vista/www
    ls -l
    cd /home/vista/www/ewd
    ls -l
    pwd


    Visiting directories

     
  • Create a working directory

    mkdir /home/vista/src

     
  • Enter in it

    cd /home/vista/src

     
  • Clone there the repositories

    git  clone  git://github.com/OSEHR/NewUI.git

    git  clone  git://github.com/OSEHR/smart-apps.git

    git  clone  git://github.com/OSEHR/m.js.git



    cloning git repositories

     
  • Go to the github pages of the corresponding repositories and Fork them into your own github user account.

     
  • Copy your private SSH Key into the /home/vista/.ssh directory

    WARNING: After this you MUST NOT share your VM, or if you do, remember to REMOVE your private Keys before you export the VM.

    You can do this from the console of your HOST machine using a command like the following:

    cd ~/.ssh
    scp luis_ibanez_kitware.pub vista@192.168.200.107:.ssh

    scp luis_ibanez_kitware vista@192.168.200.107:.ssh

    and then verifying in the GUEST (VM) that you have the file in the home ssh directory

    ls /home/vista/.ssh -l
     
  • Ensure that our key have the proper safe permissions in the VM.

    Public keys must have permissions = 644
    Private keys must have permissions = 600

    cd ~/.ssh
    chmod 600 luis_ibanez_kitware
    chmod 644 luis_ibanez_kitware.pub


     
  • Open your SSH keys using the ssh-agent.
    In the VM, use the commands:
     
  • exec  ssh-agent  bash
    ssh-add ~/.ssh/luis_ibanez_kitware


    you will be asked for the passphrase of you key.
    Type the passphrase.

    Setting up SSH keys
     
  • Add your forked repository as a remote to the one that you have now in the VM.

    For example, for the NewUI project do:

    cd /home/vista/src/NewUI
    git remote -v
    git remote add myrepo   git@github.com:luisibanez/NewUI.git
    git remote -v
    git fetch myrepo


    Of course, changing the name to the one of your own repository.

    The "git remote -v" is simply showing you the state of the remotes before and after.

    Adding Remote

     
  • The NewUI repository has a Sandbox subdirectory with training examples on using EWD with ExtJS and Sencha Touch 2.  These examples were taken from the excellent tutorials prepared by Rob Tweed at:

    http://gradvs1.mgateway.com/download/EWD_EXTJS4_Reference.pdf
    http://gradvs1.mgateway.com/download/EWD_Sencha_Touch2_Reference.pdf

    Of course, any errors in the transcription of the examples, are mine.
     
We are now ready to start writing our own code by following the tutorial examples.
 
 
This is a great point to take a break.
  • Shutdown the VM
  • Take a snapshot 
  • Restart the VM
To shutdown the VM, use the command:

           sudo shutdown -h now
 
Since we are going get messy in the process of doing the following exercises, we will definitely want to have that snapshot as a point of reference to get back to, in case our VM gets out of order. 
 
Remember, 
if your VM doesn't get messy, 
then you are not trying hard enough !!
 
Also, keep in mind that this snapshot has your private SSH Keys in it.
 
Here we name the snapshot to highlight that fact:
 
Snapshot after installing SSH keys
 
 
 

 

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