Beyond the Cloud: The Comprehensive Flexibility of FOSS May Bring Clearer Skies

Tuesday, June 29th, 2010

By CJ Fearnley

Last week’s InformationWeek has a good article on cloud computing, Cloud ROI: A Grounded View.  It seems that even with all the hype (or because of it?) most are not “running blindly” to adopt “the cloud”.  I must admit the cloud metaphor has a powerful poetic charm to it.  That is probably why it has grabbed the attention of so many over the past few years. Everything in our world is ephemeral, so there is an aptness to the concept of a “cloud”. Moreover, I too like and use cloud analogies. But I am now looking for clearer skies!  Here is a short list of my gripes about "the cloud":

  • What does “cloud computing” mean? It isn’t at all clear! Here is some data: CIO magazine cites a Forrester report that says "the number one challenge in cloud computing today is determining what it really is". CIO also reported on a McKinsey study that "found 22 separate definitions of cloud computing"! And that leads to my second point:
  • The word “cloud” is so … vacuous and amorphous …  ”A cloud:  it looks like Zeus!” only to transform in shape before your very eyes “Wait, now it looks like Aphrodite!” … and then its gone!  Is this the kind of model people should entrust with their business data?  It has no structural stability:  inherently:  it is just rapidly moving gases … far out of reach … away in the sky. What kind of business model is that?
  • Although RADLab (Reliable Adaptive Distributed Systems Laboratory) has put out some interesting papers, I was a little surprised when I read their acknowledgements in the CACM article A View of Cloud Computing.  It reads like a who’s who in cloud computing: Amazon, Google, Microsoft, Sun, eBay, Cloudera, Facebook, and so on. The original Berkeley paper has a shorter list of cloud companies funding their work. I’m sure they are maintaining their academic integrity, but it does show that they are not wholly independent. Remember what Kitty Foyle said:

    I’ve taught myself a lesson, or I hope I have: when I find myself thinking something I stop a minute and ask myself, Now who had it all figured out beforehand that was the way they wanted me to think?
    — From Christopher Morley’s novel “Kitty Foyle

  • Although the Berkeley papers raise a number of very interesting issues, none of them requires vacuous meaningless jargon to further obscure the subtleties and complexities of emerging technology trends! So my final gripe is that the name “cloud” tends to obscure what is really important even when I agree with “the cloud thinkers”.

Perhaps the most important issue “the cloud people” are missing is what might be called comprehensive flexibility. As a user of software technology, I want my computing functionality everywhere … in every imaginable format. For example, I’d like to be able to use the software that I’ve invested the time to learn to be available on my desktop (32-bit, 64-bit, Mac, Windows, or Linux), and I’d like it to work whether the Net is working or not, on my cell phone and other portable devices (again with network or not), in the data center (clustered or not), in the WAN (Wide Area Network, note that the Internet is our shared, global WAN), perhaps distributed among several hosting providers, and perhaps even provided by “utilities” (to save the trouble of maintenance and scaling costs). But I think software should be so flexible that it can live in each of those environments. Talk about utility computing: wouldn’t software have so much more utility if it worked everywhere instead of being beholden to whatever your software provider offers or what hardware you happen to have in front of you right now?

Fortunately this type of flexible software does exist. It is called Free and Open Source Softare (FOSS) and it is becoming ubiquitous. In fact, whether you know it or not, you are using FOSS software: Apache, the FOSS web server, runs this web site and indeed the majority of all web sites. Wordpress, the blogging software we use here is also “everywhere” and you can purchase it from “cloud” utility providers or install, run, and modify it yourself. The list of important FOSS software goes on and on and this blog is dedicated to helping elucidate its importance as well as the issues involved in managing it.

So I would argue that instead of letting our heads go to the “clouds” we need to ask how can we make software that works in all environments, on all hardware, and for all people? … how can we make software that is comprehensively flexible?

Xen Virtualization: Migrating 32-bit domUs to 64-bit dom0s

Friday, October 9th, 2009

By Elizabeth Krumbach

Virtualization provides the facility to run multiple isolated computer operating systems on one piece of computing hardware. There has been a huge increase of interest in virtualization technology because recent advances in multi-core technology provide significantly more computing power in each machine with ever decreasing costs. Virtualization is one of the best ways to take advantage of these big changes in hardware.

Currently, Xen is the most mature FOSS (Free and Open Source Software) virtualization technology. Although we love the idea of KVM, since it requires a special processor extension on X86 systems, it cannot work on older hardware. So for at least another few years, we think Xen is the more flexible choice for FOSS virtualization projects.

The Xen infrastructure consists of the Xen hypervisor which “runs the show”, a domain 0 (dom0) which runs a special, privileged version of the operating system (typically Linux, but NetBSD and Solaris are also supported), and one or more domain U (domU) “guest” (or “User”) operating systems. We have found that Xen is easy to configure in many situations, but we encountered some complications in running a domU on a dom0 with a different architecture.

We recently migrated some 32-bit domUs running Debian Etch (4.0) from a 32-bit dom0 to a newer 64-bit dom0 running Debian Lenny (5.0). We did a direct move (using rsync) of the Logical Volume Manager (LVM) slices from the 32-bit dom0 to the 64-bit dom0. This means we’d now be running our 32-bit Etch domUs on a 64-bit Lenny dom0.

The first question was whether this would be possible. Absolutely! 32-bit domUs have no trouble running on 64-bit dom0s, we could even use the 64-bit Xen kernel in these 32-bit systems to avoid additional kernel installations we’d need to maintain on the dom0. The second question was whether we could properly load the 64-bit kernel modules inside our domU. Again, yes! But with a caveat: the domUs were 32-bit Etch, so the 64-bit Lenny kernel modules were not simply installable via apt. We realized that copying over the .deb package for the kernel modules and running dpkg -i --force-architecture linux-modules-2.6.26...deb would not be a maintainable way to handle the kernel module updates moving forward. So we weighed our options:

1. Serve these modules via a network file system (such as NFS) to each domU on bootup.

2. Deploy a script that would notify the domU and copy the new kernel modules .deb to it for installation. We could then install the new module package at our discretion.

We decided that the first option violated our strict security policy which calls for running as few services on the dom0 as possible. Since the second solution is scriptable and therefore automatable, it fit our vision of having easily maintainable systems regardless of the underlying complexity. So we installed the 64-bit modules prior to migration so that all the proper modules would be loaded as soon as we brought up the domU on the new Dom0. The result was a flawless migration of our 32-bit domUs to the new 64-bit dom0.

Welcome to The Managing FOSS for Business Results Blog

Tuesday, October 6th, 2009

By CJ Fearnley

Welcome to our new blog.

This blog is part of a new educational initiative to foster a deeper understanding of the capabilities and issues involved with administering FOSS (Free and Open Source Software) to deliver concrete business benefits. Although our subject will sometimes become technical, we will strive to address the business benefits at the beginning of each and every post. Therefore, we are confident that this blog will prove interesting and understandable to a broad variety of leaders, managers, and technicians.

We look forward to an engaging discussion in this blog as we explore the new possibilities available to organizations to manage their IT (Information Technology) architecture with FOSS! We hope you check in regularly or subscribe to our RSS feeds.