Migrating to the Cloud: OpenStack or vCloud?

CloudComputingWe, here at The Virtualization Practice, are getting ready to have a cloud presence. Since we ‘eat our own dogfood’ with a 100% Virtual Environment, we are gearing up to move some of those workloads into a hybrid cloud. We already use some cloud resources, but now is the time to look at other workloads. Why we are moving to the cloud is three fold: how can we write about various aspects of being a tenant in the cloud, if we are not one; a recent power outage at the grid level; and a upcoming data center move. Two of these reasons are all about business continuity with the first being what we do. While we already have a cloud running within our own environment, it is time to branch out.Before last weeks OpenStack Conference, I would have said our choices were fairly slim and that we had to look for a VMware vCloud provider as we are 100% virtualized on VMware vSphere with Hyper-V, Xen, and KVM in our test lab. Now I am not so sure. It is possible to run OpenStack on top of vSphere and if such a cloud existed it would definitely be considered. However, we want a hybrid cloud and while the future is bright for cross-cloud interoperability, the fact is, the hypervisor in use still matters.

OpenStack clouds are built either upon KVM or Xen. This open source route will save on funds when creating a cloud, but does nothing to aid in the ability to move workloads into and out of the cloud when the enterprise is running anything besides KVM or Xen. OpenStack is actually in a very good position to provide a way around this, how you may ask?

OpenStack could implement the following set of additions and projects:

  • Create a Replication Receiver project which would allow OpenStack infrastructures to replicate to and from other OpenStack implementations regardless of hypervisor. This replication receiver codebase would either do the virtual disk conversion during replication, or
  • Glance should be updated to either convert virtual disks on the fly before they are launched, or
  • Create a translating filesystem that does all the work for the hypervisor during boot.

While the virtual disk contents would not change, it is the container around those contents that would need to change as well as the meta-files that define the virtual machine. Unless of course VMware, Microsoft, and the Open Source communities can define a common file format that could be used. Ideally, this should be the approach and we are working towards that with OVF. Unfortunately, OVF is just a transfer format, not a run-time format. So we are left with translation requirements.

Why is this important?

Because the obvious way to migrate to a cloud is to setup replication to move all the data into a tenants cloud instance over time and to keep it in sync until the cut-over is ready. Use of replication as a migration tool would:

  • ease migration to the cloud
  • ease migration from the cloud

Why? For  business continuity  and data protection reasons. Once in the cloud, organizations may choose other options, but getting to the cloud when you have terabytes of data to copy is not instantaneous and will take time, time when the servers and workloads need to be running. So, for an enterprise, replication receiver clouds are a must. This would definitely have provided business continuity for our own recent disaster.

Once in the cloud, we may decide to stay there and fore-go our own datacenter as just a test lab, but getting there easily and running our workloads efficiently is crucial to the successful migration to a hybrid cloud. Is OpenStack a contender? I think so, but we will have to wait for the RFP to be finished and sent out. We will make our RFP public (by adding another tab at the top entitled Cloud RFP) as well as our results, designs, and architectures. We will start with our requirements and move from there.

How would you move to the cloud? And what clouds?

Share this Article:

Edward Haletky (445 Posts)

Edward L. Haletky, aka Texiwill, is the author of VMware vSphere(TM) and Virtual Infrastructure Security: Securing the Virtual Environment as well as VMware ESX and ESXi in the Enterprise: Planning Deployment of Virtualization Servers, 2nd Edition. Edward owns AstroArch Consulting, Inc., providing virtualization, security, network consulting and development and The Virtualization Practice where he is also an Analyst. Edward is the Moderator and Host of the Virtualization Security Podcast as well as a guru and moderator for the VMware Communities Forums, providing answers to security and configuration questions. Edward is working on new books on Virtualization.

[All Papers/Publications...]

Connect with Edward Haletky:


Related Posts:

2 thoughts on “Migrating to the Cloud: OpenStack or vCloud?”

  1. Great post Ed, I’ll be watching for the RFP with interest.

    Can you clarify one thing? You’ve said that an OpenStack cloud could run on vSphere then a few sentences later stated that OpenStack clouds run Xen or KVM. Presumably vSphere is a possibility but no-one does it today?

  2. Hello Ed,

    Yes, OpenStack can run on vSphere, but the code is somewhat out of date. The instructions are there, but they are also fairly old. So getting OpenStack to work on vSphere, while possible, will need a bit of care to implement. Also, the current positioning of OpenStack is an alternative to VMware (not sure if they mean vSphere or vCloud). So possible, but given the age of the code, not used in the current implementations. Most if not all run on either KVM or Xen, with KVM being the front runner for OpenStack.

    When I can free up some time, I plan on attempting OpenStack on vSphere.

    Best regards,
    Edward L. Haletky

Leave a Reply

Your email address will not be published. Required fields are marked *

four × 3 =