Recovering Lost VMs in VirtualBox GUI

This article is a short step on how to recover you VMs in the VirtualBox GUI.

Case

I upgraded my windows machine from windows 8 to 10 and suddenly stumbled on an empty virtualbox GUI. It was almost heart wrenching for me because, I had six vm as lab. I did as much googling as I could but did not get a suitable answer. So I resulted to reading up the Virtual Machine Guide.
While this exercise was carried out on version 5.0, it works well for VirtualBox 4.0 and later.

VirtualBox GUI without existing vms entries.

Existing vm files on disk

Conditions

This process will work

• if our virtual machine guest folder has not been corrupted and still intact.
• regardless if you had to do a new installation all over again. Just ensure the version you are installing is the same as the one your previously lost.
• whether or not you lost your VirtualBox.xml file in the \.VirtualBox location.

Recovery Steps

Open the VirtualBox.xml in an text editor (I use Textpad). Search for the tag . Two things are possible - 

1. The tag has content as in but the source ("src") attribute of the entry tag is pointing to the wrong location of the VM.
2. The tag is a closed tag as in or which means that VirtualBox has lost a reference to all the VMs on the host.

Case 1

Simply edit the value of the "src" attribute to point to the correct location of the guest .vbox file.

the vbox file of the guest machine

Case 2

If the close machine registry tag is of the form , change it to the open form and enter the following entry

where
MACHINE_ID - this should be gotten from the vbox file of the guest. Open the .vbox file in a text editor and look for the uuid of the tag.

the uuid of the guest machine

The entry highlighted above is the uuid for this machine and should be the same with the uuid of the machine registry in the VirtualBox.xml.

Which ever case you use, save the file and reopen VirtualBox.

CyberSpace: the latest battle front

Stage set for the latest in cyberspace front of modern day war

I wouldn't want to call it excitement but I have this high feeling now that it has become quite official that we now have a new front line in modern day warfare - Cyberspace. How?

For the first time, a country's military has announced that it uses cyber space to gather intelligence and also attack the enemy network. It is implicit a call for all the nations of the world to begin to look into that direction.
It is just about a week ago, the Israeli military also graduated its first class of 'cyber defender', a team of high techie soldiers whose work is for fight and defend Israel's cause on the cyber space. You would expect that these guys should have received the best there is of network and system attack, defense and hacking. They are the first to officially step into this new frontline of conflict.

Also, it has been reported that the Iranian government has budgeted about $1 billion to launch herself as a force on this front. Well, who will blame her after being a victim of a likely state-organized attacks like Stuxnet, Duqu and most recently Flame.

Prior to now, we have seen virus attacks like Stuxnet, Duqu and flame as covert ways of military reconnaissance or attack or have seen hacking at a corporate level. Well, its wholly different now.

In no distant time, we will begin to see more countries formalize this unit in their countries arm force. Great days ahead, in my opinion.

IDF admits to using cyber space to attack enemies

IDF graduates first ‘Cyber Defenders’ class

Online education: ....and it happens

It doesn't come as a surprise but here we are. MIT has taken the steps of Standford University and we will be expecting their schedule any moment from now. They have already made their intention to conduct online courses known, and it is already on their website click here.

Soon the list of courses will be released. It is really gonna be a great time for me and similarly hungry people around the world.

Do java reverse engineering with cavaj

Yes, they say that reverse engineering is the science of decomposing any engineered piece with a view of composing it again, right?

Quite rightly, viewing java class file (*.class) are the best ways to reverse engineer java applications.

Severally I have been faced with a task of integrating complex systems, most of them java-based proprietary system. Since companies of proprietary system will never put resources of their product on the net, I mostly result to taking down the entire application, cross-checking log files with the decompiled class file and sooner than I imagine, I am able to imagine the system internals mentally. That is where the solution begins.

You may check cavaj for yourself here.

We should note that cavaj is not good for those who don't yet have basic understanding of java programming language. The code produced by cavaj is not equivalent to the java source that produced it. No annotations, documentations, String addition with the "+" operator are changed to StringBuilder(...).append(...) mechanism, inner class are changed to class_name$inner_class_name, anonymous inner class are changed to class_name$number (like 1,2,..), constants are replaced with their values and many others like that.

For those who love reverse engineering in java, enjoy cavaj.

Standford Online Engineering course: More classes

Surely, we are seeing a new trend that will define education in the nearest future and gladly I am a participant.

The Standford Engineering Everywhere (see) just added me courses to the list of courses announced. They include

January 2012

1. Anatomy with Sakti Srivastava
2. Making Green Buildings with Martin Fischer
3. Model Thinking with Scott E. Page

Febuary 2012

1. Computer Security with Dan Boneh, John Mitchell and Dawn Song *

March 2012

1. Information Theory with Tsachy Weissman

* this is the first time, I am noticing a Professor from another university other than Stanford participating in this programme - Professor Dawn Song. Things are changing.

Those interested in medicine, Electrical and civil engineering can now join us in this education offering.

Once again THANK YOU STANDFORD - you are the best.

We may not have the privilege of having a Standford degree but now we can have the Standford knowledge.

Stanford Free Engineering Courses for 2012

Below is a listing of all the Standford free Engineering courses online. They are grouped into category of commencement period and are arranged alphabetically.

January 2012

1. Cryptography with Dan Boneh
2. Design and Analysis of Algorithms I with Tim Roughgarden*
3. Game Theory with Matthew Jackson and Yoav Shoham
4. Human-Computer Interaction with Scott Klemmer
5. Machine Learning with Andrew Ng **
   
6. Natural Language Processing with Chris Manning and Dan Jurafsky
7. Probabilistic Graphical Models with Daphne Koller
8. Technology Entrepreneurship with Chuck Eesley

February 2012

1. Computer Science 101 with Nick Parlante
2. Software Engineering for Software as a Service with Armando Fox and David Patterson
3. The Lean Launchpad with Steve Blank

* - the name of the course - "Design and Analysis of Algorithms I" and I wonder if somehow there is a "Design and Analysis of Algorithms II" coming up later.
** - Machine learning with Andrew Ng is going to be a similar course with the one previously taken on the site www.ml-class.org

This is a whole lot of stuff coming up for 2012.
The intention is clear and awesome - you get to learn 9 strong engineering courses and 2 entrepreneurship courses to help you get to the market.

First quarter of 2012 is really gonna be fun.

We may not have the privilege of having a Standford degree but now we can have the Standford knowledge.

Stanford Online Engineering Courses: Machine Learning

I have really kept things musing within me about the recent free online course offered by Stanford University's School of Engineering online through the Standford Engineering Everywhere programme. Courses currently on-going include

1. Machine Learning with Professor Andrew Ng
2. Introduction to databases with Professor Jennifer Widom
3. Introduction to Artificial intelligence with Prof. Sebastian Thrun and Peter Norvig

I was initially tempted to take all the course (with less participation in the DB course) but going live on the course, I knew that sometimes you need both hands to squeeze all the juices out of the orange. So, I stayed on Machine Learning and it has been very fantastic.

Not only has the course opened up areas in computing that were faint and becoming increasing obscured, it has completely laid open my cognition and sense of recognition. I was already getting my hands dirty with programming in R but Professor Ng pointed strongly encourage octave and I just got better with the two.

It is worth noting the wonderful lecturing skills of Professor Ng and whether or not he reads this, I would like to say THANK YOU to him and to Standford School of Engineering.

We may not have the privilege of having a Standford degree but now we can have the Standford knowledge.