OpenNebula Conference 2014

This year’s edition of the international OpenNebula Conference is packed with an amazing agenda, If you want to learn about Cloud Computing in general, and OpenNebula in particular. If you are familiar with the software or even an active user or contributor to the project, willing to hear and learn how other members of the community bend OpenNebula for their infrastructure needs, this is the place to be!

Want to know what to expect? Last year’s conference was an absolute success, with fruity presentations of long time users of OpenNebula, and with various use cases that, we can confess, largely surprised the OpenNebula team for their artfulness. It is always a pleasure to see how people are using OpenNebula! But do not take our word for it, but rather take a look at the recorded video sessions of all talks of 2013, skim through the slides of the different keynotes and talks and take peak at the various pictures taken during the conference and the evening event.

OpenNebulaConf 2014 is shaping even better this year. Take a look at the highlights from the final agenda:

This edition of the conference is just around the corner, happening next 2-4 December in Berlin, Germany. If you are interested in attending the conference, we entreat you to register swiftly, since seats are limited and only a few are left.

See you in Berlin!


The OpenNebula project is proud to announce the availability of OpenNebula 4.10 Beta (Fox Fur). This release ships with several improvements in different subsystems and components. But, more importantly, it features a little revolution in shape of vCenter support.

This is the first OpenNebula release that allows to automatically import an existing infrastructure, since the new vCenter drivers allow to import Clusters and Virtual Machines from a vCenter installation, significantly smoothing the set up curve. The concept of the vCenter drivers is akin to the hybrid cloud approach in the sense that OpenNebula will delegate a number of aspects to vCenter, instead of pursuing the management of almost every aspect as it traditionally does with the three supported hypervisors: XEN, KVM and VMware ESX. OpenNebula will use pre defined Virtual Machine Templates existing in the vCenter set up to launch Virtual Machines, very much like it does in its hybrid drivers to access Amazon EC2, IBM SoftLayer and Microsoft Azure, although offering extra features like for instance VNC support and more lifecycle actions.

We are aware that in production environments, access to professional, efficient support is a must, and this is why we have introduced an integrated tab in Sunstone to access OpenNebula Systems (the company behind OpenNebula, formerly C12G) professional support. In this way, support ticket management can be performed through Sunstone, avoiding disruption of work and enhancing productivity.

Zendesk Support

Finally, several improvements are scattered across every other OpenNebula component (check the full list of changes in the development portal):

  • a new iteration for the features introduced in Lemon Slice to the OpenNebula networking system
  • improvements in the hybrid drivers, including better Sunstone support.
  • persistency of  snapshots across the VM lifecycle (this allows to revert an snapshot after a VM migrate operation, for instance).
  • the ability to change the ISO file attached to a CDROM media dynamically.
  • and many other bugfixes that stabilized features introduced in Lemon Slice.

As usual OpenNebula releases are named after a Nebula. The Fox Fur Nebula (IC 3568) is located in Monoceros and included in the NGC 2264 Region.

The OpenNebula team is now set to bug-fixing mode. Note that this is a beta release aimed at testers and developers to try the new features (not production environments) and send a more than welcomed feedback for the final release.

Features for network extension model refined in OpenNebula 4.10 were funded by BlackBerry in the context of the Fund a Feature Program.

Relevant Links


Next week the Linux Foundation conferences LinuxCon + CloudOpen + ELC-E Europe 2014 will take place in Dusseldorf. I’ll be there Wednesday 15th at CloudOpen to give a talk about the OpenNebula cloud provisioning model and a two-hour hands-on tutorial on building clouds with OpenNebula. Here are the links to my talks:

If you are there and have questions or want to talk about OpenNebula or any other topic you can meet me before or after the sessions. You can reach me at my twitter account @thevaw or with my email address (jfontan AT this domain) if you want to plan ahead.

See you in Dusseldorf!

Next version of OpenNebula -4.10- is going to be a special release. It will be the first release that will be able to automatically import an existing infrastructure. This will become a reality with the new vCenter drivers and the auto import feature of Clusters and Virtual Machines from a vCenter installation.

The concept of the vCenter drivers is akin to the hybrid cloud approach in the sense that OpenNebula will delegate a number of aspects to vCenter, instead of pursuing the management of almost every aspect as it traditionally does with the three supported hypervisors, XEN, KVM and VMware ESX. These aspects are the storage management, scheduling among ESX hosts -both of which are left to VMware DRS component, although the OpenNebula scheduler still choses the vCenter cluster where the VM should be instantiated in- and network management. OpenNebula will use pre defined Virtual Machine Templates existing in the vCenter set up to launch Virtual Machines, very much like it does in its hybrid drivers to access Amazon EC2, IBM SoftLayer and Microsoft Azure, although offering much more features like for instance VNC support and more lifecycle actions supported (in fact, all of them except migrate).

vCenter Integration Architecture

OpenNebula vCenter Integration Architecture

This upcoming OpenNebula integration will leverage vCenter advanced features such as vMotion, HA or DRS scheduling provided by the VMware vSphere product family. On top of it, OpenNebula will expose a multi-tenant, cloud-like provisioning layer, offering virtual data centers, datacenter federation or hybrid cloud computing to connect in-house vCenter infrastructures with public clouds. In this manner, adopters will take a definitive step toward liberating their stack from vendor lock-in.

 The Technical View 

The VMware vCenter drivers enable OpenNebula to access one or more vCenter servers that manages one or more ESX Clusters. Each ESX Cluster is presented in OpenNebula as an aggregated hypervisor, i.e. as an OpenNebula host. Note that OpenNebula scheduling decisions are therefore made at ESX Cluster level, vCenter then uses the DRS component to select the actual ESX host and Datastore to deploy the Virtual Machine.

As the above figure shows, OpenNebula components see two hosts where each represents a cluster in a vCenter. You can further group these hosts into OpenNebula clusters to build complex resource providers for your user groups and virtual data centers in OpenNebula.

Virtual Machines are deployed from vCenter VM Templates. There is a one-to-one relationship between each VMware VM Template and the equivalent OpenNebula Template. Users will then instantiate the OpenNebula Templates where you can easily build from any provisioning strategy (e.g. access control, quota…). Therefore there is no need to convert your current Virtual Machines or import/export them through any process; once ready just save them as VM Templates in vCenter. After a VM Template is cloned and booted into a vCenter Cluster it can access VMware advanced features and it can be managed through the OpenNebula provisioning portal or through vCenter (e.g. to move the VM to another datastore or migrate it to another ESX). OpenNebula will poll vCenter to detect these changes and update its internal representation accordingly.

Check out the following screencast to see how easy it is to import an existing vCenter infrastructure into OpenNebula (use full screen and the higher resolution settings for optimal view).

 The Enterprise View

These drivers are oriented to companies willing to keep VMware management tools, procedures and workflows. For these companies, throwing away VMware and retooling the entire stack is not the answer. However, as they consider moving beyond virtualization toward private cloud computing, they can choose to either invest more in VMware, or proceed on a strategically rewarding path of open.

So stay tuned for the upcoming OpenNebula 4.10 for a new standard for easiness, efficiency and robustness in the cloud computing paradigm.

We want to let you know about what we are up to with the main news from the last month regarding the OpenNebula project, including what you can expect in the following months.


The OpenNebula Team is working full steam ahead towards the 4.10 version, in order to improve features launched in Lemon Slice and include some new ones of its own.

Probably the most important novelty would be complete integration with VMware vCenter. OpenNebula 4.10 will be able to interact with a farm of ESX servers without contacting them individually, but rather through their associated vCenter. This has been requested many times, specially from corporate institutions where security and simplicity of management is a must have. This feature is still on the works, but it already have some killer characteristics like clusters and VM template automatic import from an existing vCenter set up with no downtime!

vCenter Create Host dialog

Other aspects we are polishing is the network subsystem, with security improvements made to reservations and VNETs and the authorization subsystem -it will be possible to create short lived tokens to login into OpenNebula-. We would like to thank BlackBerry for their support funding these features. Moreover, a myriad of bugs are being addressed to make the upcoming 4.10 release rock solid. You can check the list of targeted bugs and desired features tackled for OpenNebula 4.10 in the development portal.

This last month the OpenNebula Team released a new version of the AppMarket, compatible with OpenNebula 4.8 that also solves issues reported by the community.


More than 2,000 users took part of the project’s last survey. Thanks to all the people that provided this valuable feedback, this information is key to keep improving your favourite CMP.

The survey shows some interesting facts, for instance that OpenNebula has been downloaded more than 200,000 times from the project site. Also, that most of the installations are to build private clouds as well as (and we take huge pride in this), more than half are used to run production workloads. We are really happy with so many people trusting their sensitive data and computations to OpenNebula! There are lots of good information about how the OpenNebula cloud world is shaped, take a look and let us know if you have any hindsights or you want to comment about it.

Autumn is here, and it shows as more and more people stays indoors and occasionally praise OpenNebula. Also, they go out and talk about integrations, like for instance this talk about OpenNebula and Puppet, killer combination. Our friend Carlo Daffara keeps pushing OpenNebula to its limits, and we are extremely grateful for that, as well as for the comparison with other CMPs.

Are you Perl savvy? Check out this perl library to access OpenNebula RPC interface!


This year’s OpenNebula Conference, to be held in Berlin 2-4 of December, 2014 is approaching fast. The final agenda is now available at the conference page. This years will offer the chance to learn how folks from PuppetLabs, E-Post, Deloitte and many other companies are using OpenNebula. Moreover, check out the venue for the evening event, lush isn’t it?. If you want to repeat or find out how it is for yourself, save the date and register!.

Moreover, if you are interested in reaching a wide cloud audience, check the sponsorship opportunities for the OpenNebula Conference 2014.

You may be interested in how the jointly OpenNebula TechDay held last month went in Timisoara, Romania, a great success with a great audience!.


Our project director went to give a talk on OpenNebula and it’s benefits for SMEs on Extremadura, a region of Spain traditionally very friendly towards open source. We would like to thank CENATIC for inviting us!

We have upcoming TechDays in future months, if you are interested in OpenNebula you can check the project page. The next TechDay would be held in beautiful Santiago de Compostela, with local government and scientific computer science institution giving talks about their use of OpenNebula.

Remember that you can see slides and resources from past events in our Events page. We have also created a Slideshare account where you can see the slides from some of our recent presentations.

If there’s one thing that I got asked a lot is a summary of my viewpoint on “why you choose opennebula”, after my presentation at the last OpenNebulaConf. Basically the answer is always “it depends on what you’re looking for” but it rarely suffices, so I take advantage of the invitation by Ignacio Llorente to write a few words on that. Let’s start with an image that explains how people usually views the debate:


And – let’s be clear – it does not really convey the fact that OpenNebula and OpenStack are both terrific project with slightly different needs and use cases, and so this comparison is probably useless. After all, do we really say that we can’t have both Apache and Nginx as web servers? Who said that we can’t have both, in their respective market niches?

In my view, OpenStack is a toolkit for creating sophisticated Infrastructure-as-a-Service platforms, and is composed of several top level projects and many more ancillary pieces, a view that is shared by many others (for example Monty Taylor, or Jay Pipes) that can be summarily shown as:


Talking about “an OpenStack cloud” is thus quite indefinite, as it may be composed of just three pieces or thirty. Another defining aspect is the overall scalability, that implies that (just because there are lots of different pieces, connected in many different ways) there are lots of knobs. Lots.


Well, OpenStack probably needs them all.


And – just to be clear – a very large OpenStack installation probably needs most of them, since they need to provide components that must be usable and deployable in innumerable different conditions and combinations.

OpenNebula is structurally different: it is much more a finished product, with a modular structure that covers a subset of the OpenStack projects, with a much smaller set of variables and knobs:

OpenStack component OpenNebula equivalent
Compute (Nova) builtin
Object Storage (Swift) no equivalent
Image Service (Glance) builtin
Identity (Keystone) builtin
Dashboard (Horizon) SunStone
Networking (Neutron) builtin
Block Storage (Cinder) builtin+plugins
Telemetry (Ceilometer) builtin
Orchestration (Heat) flow
Database Service (Trove) no equivalent
Data processing (Sahara) no equivalent
Bare metal (Ironic) no equivalent
Queue service (Zaqar) no equivalent
Key management (Barbican) no equivalent
DNS Services (Designate) no equivalent

Most of the higher level services do have no equivalent in OpenNebula, and it’s mostly by design – if you need a service you add it through an external VM that provides what you need. For example, if you need an object storage service you can use Riak, Ceph, Walrus, Gluster, Skylable are among the first that come to mind, all with different advantages and disadvantages (and you can even use swift inside of an OpenNebula VM, by the way :-))

The “all in one” approach of OpenNebula also simplifies common management operations, like recovery from failover. OpenStack needs external automation or a manual intervention; as an example, to recover from a total fault on a compute node:

“If a compute node fails and won’t be fixed for a few hours (or at all), you can relaunch all instances that are hosted on the failed node if you use shared storage for /var/lib/nova/instances. To do this, generate a list of instance UUIDs that are hosted on the failed node by running the following query on the nova database:
mysql> select uuid from instances where host = ‘’ and deleted = 0;
Next, update the nova database to indicate that all instances that used to be hosted on are now hosted on
mysql> update instances set host = ‘’ where host = ‘’ and deleted = 0;
After that, use the nova command to reboot all instances that were on while regenerating their XML files at the same time:
# nova reboot –hard <uuid>
Finally, reattach volumes using the same method described in the section Volumes.”

(from OpenStack Operations Guide, sep. 2014, page 140)

Even after a compute node reboot, you may have to handle things properly:

“After the compute node is successfully running, you must deal with the instances that are hosted on that compute node because none of them are running. Depending on your SLA with your users or customers, you might have to start each instance and ensure that they start correctly. … You can create a list of instances that are hosted on the compute node by performing the following command:
# nova list –host –all-tenants
After you have the list, you can use the nova command to start each instance:
# nova reboot <uuid>”

OpenNebula on the other hand manages the same thing with the fault hooks, mostly managing things in an automated way. Other aspect are extremely simplified in OpenNebula, like action/condition triggers, where OpenStack Heat is certainly more complete and sophisticated than the probes available within OpenNebula.

Another aspect is size: OpenNebula is one tenth of OpenStack in terms of lines of code – 1841Klines for OpenStack vs. 193Klines for OpenNebula (data from J.G.Barahona, “the quantitative state of the open cloud”, OSCON 2014) which means that changing, adapting and simply looking at the code to understand it is ten times easier and cheaper as well.


If we look at the features that are expected both from devops and enterprise users (as defined by the fine folks at the 451 group) we can see that what is looked for is a set of features like these:

Feature Audience
Supports hybrid cloud networking (multi-vendor, public, hosted) DevOps and enterprise business users
Supports private cloud offerings Both
Supports vendor and user service blueprints Enterprise business
Supports VM provisioning, HA, scaling, recovery DevOps
Integrates with developer tools (such as Chef or New Relic) DevOps
Offers a self-service portal, service catalog DevOps
Integration/migration (transformation engine) DevOps
Provides workload placement recommendations Enterprise business
Offers consumption management/optimization recommendations Enterprise business
Supports role-based access control/security Both
SaaS and on-premises license models Enterprise business
Offers app monitoring and system tool extensions (patching, backup, OS monitoring, etc.) Both

source: 451 group “Cloud Management Platforms: a comparison of product categories”

And it’s easy to see that apart for the last line (where probably the only open source platform with said features is ManageIQ) everything else is more or less covered by both.

The end result is that OpenStack and OpenNebula should be seen as complementary offerings – if you need a toolbox, or the features of some or all the many components offered by the OpenStack ecosystem just go there. Lots of people will help you in building your cloud, the amount of activity and enthusiasm is amazing and beautiful. If you need something that can be deployed, understood and used in a few hours (without sacrificing scalability or core features) look at OpenNebula.

The open cloud does have space enough for both.