OpenStack vs OpenNebula. What are the differences?

OpenNebula and OpenStack are two well-known open-source platforms for managing cloud infrastructure. Both let you centrally manage virtual machines, storage and networks. However, they differ quite a bit in terms of complexity and where they’re typically used.

What are OpenNebula and OpenStack used for?

OpenNebula and OpenStack are both designed to help you build and manage your own cloud infrastructure. You can use them to run virtual servers, set up networks, and allocate storage as needed, similar to commercial cloud providers. Both platforms support private clouds in your own data centre as well as hybrid cloud setups that combine internal and external resources.

OpenNebula is commonly used by small to medium-sized businesses and research institutions that want a manageable virtualisation platform. It’s designed to be easy to set up and straightforward to use. Typical use cases include internal server environments, test setups, or virtual desktop infrastructure (VDI).

OpenStack, by contrast, is mainly used in large data centres and by cloud providers. It’s highly modular and built to handle very large infrastructures. This makes it a strong fit for enterprise environments or even public clouds. Many hosting providers rely on OpenStack as the foundation for their cloud services.

Both platforms aim to do the same thing, but they take very different approaches. OpenNebula focuses on simplicity and efficiency. OpenStack prioritises flexibility and scalability but is more demanding to set up and maintain.

What are the system requirements and infrastructure differences?

Both OpenNebula and OpenStack typically run on Linux servers and are designed for data centre environments. In most cases, they’re deployed on powerful physical machines that act as virtualisation hosts. These setups often use bare metal servers meaning the software runs directly on physical hardware without an additional virtualisation layer underneath.

OpenNebula can run on just a few servers and works well even in smaller clusters. In simple setups, even a single server can be enough for basic testing. It has relatively modest resource requirements, which makes it a good fit for smaller IT environments. OpenStack, on the other hand, usually requires multiple servers because its different components run separately. A typical setup includes controller nodes, compute nodes, and storage nodes. This significantly increases hardware requirements compared to OpenNebula.

Both platforms support common hypervisors such as KVM, which are used to run virtual machines. They also offer some level of container integration:

• OpenStack: through projects like Magnum, Kubernetes, or Zun
• OpenNebula: via LXC/LXD, Kubernetes integration

Networking is typically handled using software-defined networking.

How does key features and usage compare?

OpenNebula and OpenStack take very different approaches to building cloud infrastructure. OpenNebula focuses on a simpler, more integrated platform, while OpenStack is made up of many separate components. These design choices affect everything from installation to day-to-day operations.

Architecture and complexity

OpenNebula’s architecture is much more compact in terms of design. Many features are built into the platform, so you don’t need as many additional services. This makes things easier to understand and manage. OpenStack is made up of many separate components that handle virtual machines, networking, and storage. These components communicate via APIs, which makes the platform highly flexible, but also more complex.

Setting up OpenStack usually takes more planning, and configuration errors can have a bigger impact. However, it also allows for highly customised environments. This means OpenNebula is a good choice if you want something simpler and easier to manage. That’s why OpenNebula is generally easier for beginners to get started with. OpenStack is better suited for teams that already have experience running complex infrastructure.

Scalability

OpenNebula works well for small to medium-sized clusters and can scale to several thousand virtual machines. For many organisations, that’s more than enough. OpenStack was designed for large-scale cloud environments. It can manage not just thousands of virtual machines, but entire data centres.

As your infrastructure grows, OpenStack becomes increasingly valuable. It also offers advanced automation and multi-tenancy features, allowing many users to work in parallel without issues. OpenNebula can scale too, but you may run into practical limits sooner. For most typical enterprise setups, though, this isn’t a major drawback.

Operation and management

OpenNebula has a clear and user-friendly web interface. Many functions are easy to find, and the overall structure is intuitive. Most admins get the hang of it pretty quickly. OpenStack also provides web interfaces like Horizon, but it’s more focused on APIs. Many tasks are handled through automation or scripts, which gives you more flexibility but also requires deeper technical knowledge.

OpenNebula is a good fit for traditional server administration with more direct control. OpenStack is often used in automated DevOps environments. Because of that, the day-to-day workflows can look very different. For smaller teams, OpenNebula is usually easier to manage.

Typical use cases

OpenNebula is often used in mid-sized companies for internal cloud environments or virtualisation platforms. It’s also popular in universities and research projects. OpenStack is used by large enterprises and cloud providers. It works especially well for large-scale infrastructure projects. Many hosting environments are built on OpenStack, which also has a large, active developer community.

What are some alternatives to OpenNebula and OpenStack?

In addition to OpenNebula and OpenStack, there are other platforms you can use to build your own cloud infrastructure. One popular option is Proxmox, which is widely used for virtualisation and smaller private cloud setups. If you compare OpenNebula vs Proxmox, you’ll see Proxmox is generally easier to set up, while OpenNebula offers more built-in cloud functionality. You can also use OpenNebula to build private clouds.

Apache CloudStack is another complete cloud management platform. If you compare OpenNebula and CloudStack, CloudStack sits somewhere between OpenNebula and OpenStack: it’s powerful, but less complex than OpenStack.

Commercial solutions like VMware vSphere or Microsoft Azure Stack also exist. These comes with professional support and a wide range of features, but they’re typically more expensive than open-source options.