Alternative virtualization solutions when OpenStack is too much

Plan B

The Veteran: Proxmox

If you think Pacemaker is too much of a hassle, you'll probably be happier with Proxmox. From today's perspective, Proxmox can almost be considered a kind of veteran in the virtualization business, and what the project has achieved over the past few years certainly speaks for itself. In many respects, Proxmox is even on a par with its competitor VMware – but let's take things one step at a time.

At the heart of Proxmox was the desire to create a simple way to manage virtual instances and their storage needs. When the first versions of Proxmox saw the light of day, neither oVirt nor OpenStack were as advanced as they are today, and a kind of race for users' favor emerged between Proxmox and oVirt in particular. As things stand, Proxmox might even have won the honors because the product is now seen as the logical VMware replacement and successor to oVirt in many places.

In terms of functionality, Proxmox (Figure 4) really doesn't need to hide its light under a bushel. The key to the solution is a dedicated management plan that can be rolled out to one or dozens of systems, with the systems handling the coordination tasks themselves. One major strength of the solution is its web interface, which gives even less experienced users access to quite a few functions in the background. Thanks to appropriate rights management and role-based access control (RBAC), the Proxmox UI can also be used for basic self-servicing.

Figure 4: Proxmox is a genuine veteran when it comes to virtualization, but today it coexists well with other solutions (e.g., Ceph) and even rolls them out on its own in some cases. © Proxmox

Users who found tinkering with Pacemaker too much can enjoy complete Pacemaker handling as part of the Proxmox package. Compute nodes can be defined as HA nodes, and Proxmox takes care of rolling out and configuring the required HA services on the affected systems in the background.

Moreover, the integration of various storage back ends is legendary. For HA, for example, support for the distributed replicated block device (DRBD) replication solution was offered as early as a decade ago. Today, people tend to rely on Ceph, which Proxmox can even automate when called on to do so. Of course, this only works if you have the right hardware in place. The same applies to your own storage replication stack based on ZFS if no hardware is available for Ceph or you do not want to use the product.

Beyond that, Proxmox leaves little to be desired in terms of functionality. For storing templates for virtual instances, Proxmox supports KVM virtualization, as well as container virtualization that is based on Linux containers (LXC). Proxmox handles containers and VMs as equivalent virtual instances. Its own setup is also manageable. The solution is up and running quickly, not least thanks to a comprehensive installation guide on the project page.

The provider's distribution policy causes many an administrator to frown – although this attitude is not totally fair. Proxmox virtual environment (Proxmox VE) is available under a free license and can be obtained as open source software from the provider's GitHub directories completely free of charge. However, building packages is then up to the user, and it is this step that many companies want to avoid.

Those who are only keen on the packages and do not want any support from the manufacturer are asked to pay a EUR95 (~$93) subscription fee per year and CPU socket, so a setup with four sockets would cost EUR380 (~$372). Given Proxmox's impressive feature set and ease of installation, this does not seem excessive.

OpenNebula

OpenNebula belongs on any list of OpenStack alternatives. The product has basically acted as a kind of anti-OpenStack from the very beginning. Far less complexity, simpler UIs, easier operation, and more automation out of the box are just some of the promises vendor OpenNebula uses to attract customers – and OpenNebula actually delivers on most of its promises.

Automated installation of OpenNebula (Figure 5) with all the required components is an easy and quick process – at least if you get your planning right up front, including the web interface, which is so important for genuine cloud computing, as well as any software that might be required in the background, such as Ceph. Basic SDN functionality with OpenDaylight or Open Virtual Network (OVN) is now available, as is comprehensive handling of storage volumes. The provider garnishes the whole thing with neat administration of VM templates and an intuitive web interface, including multitenant capability. All told, OpenNebula is a genuine alternative, especially for smaller cloud setups.

Figure 5: OpenNebula has been successfully marketing itself as a sort of anti-OpenStack for years. If you are fed up with the excessive OpenStack complexity, you will most likely find what you are looking for here. © OpenNebula

Some people might wonder why OpenNebula shouldn't replace OpenStack completely. As usual, the devil is in the details. In some ways, OpenNebula is what many enterprises once hoped OpenStack would be – a virtualization solution that is not overly complicated and offers basic cloud functionality, automation, and self-service.

OpenStack has never been able to live up to this claim, if only because many large telcos and other companies had a say in the fate of the project and sometimes unrestrainedly asserted their own interests. The result was the kind of complexity that exceeds the capabilities and possibilities of smaller setups a priori. For most small environments, OpenStack can simply do too much. OpenNebula offers an attractive alternative, offering sufficient numbers of useful features for small environments without being overly complex.

Conclusions

As this article shows, you rarely will have to resort to OpenStack. OpenStack has its sweet spot in large corporations that are becoming platform providers and need to offer huge virtualization environments in the process. However, this is not the case for most smaller companies, so check before you commit. The first step in introducing a new virtualization environment should always be to document your needs accurately.

If you don't need most classic cloud functionality, a DIY solution with Pacemaker, Libvirt, and Qemu is a valid option, because it is easily manageable. If you are looking for a successor to VMware, Proxmox and oVirt are logical first choices. If you really need to create a kind of cloud, but without the overburdening complexity of OpenStack, OpenNebula is likely to be the environment of choice. This example once again demonstrates the strength of the F/LOSS community, which has a ready-made solution for problems of any size.

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