What Is OpenStack
OpenStack is an open-source platform for building and managing private and public clouds. It provides a collection of services for compute, networking, and storage that work together to deliver infrastructure on demand.
Created in 2010 through a joint effort between Rackspace and NASA, OpenStack has evolved into a modular framework used by organizations that want control over their cloud environments. It can orchestrate virtual machines, containers, and bare metal resources through a unified API.
Unlike a traditional virtualization platform, OpenStack operates at a higher layer by coordinating multiple virtualization technologies and integrating with other infrastructure tools. Its modular design allows deployments to start small and expand as requirements grow, whether for internal development workloads, public cloud services, or high-performance research computing.
Understanding OpenStack
At its core, OpenStack is a framework made up of multiple coordinated services. Each service handles a specific function, such as provisioning virtual machines, managing storage volumes, or configuring network connectivity, and all services work together to present a unified cloud platform.
The architecture is modular, meaning deployments can include only the services needed for a given use case. These components communicate through standardized APIs, which makes it possible to scale or replace parts of the system without disrupting the rest.
OpenStack is designed to integrate with a wide range of hypervisors, storage systems, and networking technologies. This allows organizations to tailor their cloud environments to different workloads and hardware. A business might deploy it to provide internal development environments, while a research lab might use it to run compute-intensive simulations.
Common misconception:
Some view OpenStack as a single piece of software or a direct alternative to a hypervisor. In practice, it orchestrates and manages existing virtualization, storage, and networking systems rather than replacing them.
Core Components of OpenStack
OpenStack is organized into services, each responsible for a specific function within the cloud environment. While there are many optional projects, five core services form the foundation of most deployments:
Service | Function | Example Use |
---|---|---|
Nova | Manages compute resources by provisioning and controlling virtual machines or bare metal servers. | Launching a virtual machine for a development environment. |
Neutron | Provides networking as a service, including IP address management, routing, and network isolation. | Creating an isolated network for a multi-tier application. |
Cinder | Handles block storage, offering persistent volumes that can be attached to compute instances. | Attaching a volume to a database server for data storage. |
Keystone | Manages authentication and authorization for all OpenStack services. | Controlling user access to specific projects or resources. |
Horizon | Web-based dashboard for interacting with OpenStack services. | Administrators or users creating instances through a browser. |
These core services operate together to deliver a functioning cloud. For example, when a user launches a new virtual machine, Nova provisions the compute resource, Neutron sets up the networking, Cinder may attach a storage volume, and Keystone verifies the user's permissions. Horizon can provide a graphical interface for the same workflow.
Additional projects, such as Swift for object storage or Heat for orchestration, can extend the platform's capabilities, but they are not required for a basic deployment.
Setting Up OpenStack
Deploying OpenStack is not a matter of spinning up a few VMs and running an installer. It is a large-scale engineering effort that touches almost every layer of infrastructure. Even small clusters require planning across hardware, networking, storage, and security, and you need a team with the right skills to make it all work.
The people you need
An OpenStack rollout will stress-test your team's breadth of knowledge. You will need systems administrators who are at home deep in Linux internals, comfortable tuning kernels, and quick to diagnose why a service will not come up after a reboot. Networking expertise is critical too. You need people who can go beyond basic interface configuration and who understand VLANs, routing, trunking, and how overlay networks like VXLAN behave under load.
Storage is another specialty you cannot treat as an afterthought. Whether you are integrating with Ceph, an enterprise SAN, or a mix of local disks and NFS, you need people who can plan capacity, monitor performance, and troubleshoot latency. Security and identity management are equally important. Someone will have to configure Keystone, manage TLS certificates, and define access rules in a way that balances usability with protection. Because OpenStack is made of many distributed services, having staff comfortable with automation tools like Ansible or Helm will save you from days of repetitive manual work. Finally, be prepared for troubleshooting across multiple layers. When a VM launch fails, the root cause could be in the compute node, the scheduler, the message queue, or the database.
The questions you must answer before deployment
Before you even rack the first server, you should have answers to some hard questions. How much compute, storage, and network throughput will you need now and in the next two years? Will your control plane be redundant, and if so, how will you cluster databases and message queues? How will you separate management, tenant, and storage networks, and do you have enough address space reserved for each?
You will also need to decide which hypervisor and storage backends you will support and whether your networking gear can handle the level of segmentation OpenStack expects. Upgrades are not optional. How will you roll them out without downtime? Monitoring and logging should be in place from day one, ideally with Prometheus, Grafana, or an ELK stack, because finding the cause of a problem without historical data is guesswork. And no matter how good your uptime is, something will eventually fail, so you need a disaster recovery plan that covers backups, restores, and realistic recovery objectives.
Minimum infrastructure requirements
- Compute resources: Multi-core processors with hardware virtualization, ECC memory, and enough RAM to comfortably support both the control plane and workloads.
- Storage: Fast, reliable disks for control plane databases and high-throughput storage for workloads.
- Networking: Multiple NICs for isolating management, tenant, and storage traffic, along with switches and routers you can configure to match your network plan.
Deployment options
Option | Purpose | Typical Use |
---|---|---|
DevStack | Lightweight, script-based deployment for testing and development. | Local lab environments, learning exercises. |
Packstack (RDO) | Installer for Red Hat-based systems, suitable for small to medium deployments. | Proof-of-concept or limited production use. |
Kolla-Ansible | Containerized deployment and management of OpenStack services using Ansible. | Production environments with container-based control planes. |
OpenStack Charms (Juju) | Declarative deployment on Ubuntu using Canonical's tooling. | Automated deployments with integrated service management. |
TripleO | OpenStack-on-OpenStack installer for large-scale, production-grade deployments. | Enterprise-scale production clusters. |
Best practice:
Start with a small, isolated, non-production deployment to confirm your architecture and practice operational procedures. Use it to test failure recovery, scaling, and upgrades before rolling into production.
Managing OpenStack
Running OpenStack day to day is often more challenging than deploying it. Once the control plane is online and workloads are running, the real work begins. The focus shifts to keeping the system stable, secure, and performing well over time. Managing OpenStack is about more than responding to problems. It requires active monitoring, regular maintenance, and a disciplined approach to changes.
The ongoing responsibilities
Upgrades are unavoidable. OpenStack follows a steady release cycle, and skipping too many versions can make future upgrades painful or even impossible without a rebuild. A well-run deployment has an upgrade plan that covers rolling updates to controllers, database schema migrations, and compatibility testing for client tools. This planning is essential because upgrading a live cluster without preparation is one of the fastest ways to break production workloads.
Monitoring is just as critical. You need visibility into both infrastructure health and service-level metrics. That means tracking CPU, memory, and disk usage on nodes, as well as keeping an eye on Nova scheduler queues, Neutron agent status, and API response times. Tools like Prometheus and Grafana can help, but they require tuning to avoid information overload. Logging should be centralized, indexed, and searchable so that a single failed API request can be traced across multiple services without jumping between servers.
Scaling is another constant concern. If you add compute nodes, they must be integrated into Nova and networked properly in Neutron. Adding storage means expanding Cinder backends and updating quotas. Each scaling event should be treated as a controlled change, not a quick tweak, because a mistake can ripple through the entire deployment.
When things break
Troubleshooting OpenStack is rarely about a single failed service. Problems often span multiple components. For example, a failed instance launch might stem from a missing network in Neutron, a capacity limit in Nova, or a message queue issue that prevents the scheduler from communicating. Effective operations teams have runbooks for these situations, with steps for gathering logs, testing component health, and isolating the fault.
Operational best practices
- Keep test and staging environments that mirror production for validating changes.
- Apply security patches to both OpenStack services and the underlying OS on a regular schedule.
- Rotate and manage credentials for Keystone, message queues, and databases.
- Document your network, storage, and compute topology so new operators can onboard quickly.
- Automate wherever possible to reduce human error, especially for repetitive tasks like node provisioning or service restarts.
A stable OpenStack environment comes from continuous attention. The complexity of its interconnected services means that ignoring routine maintenance increases the risk of outages. Teams that approach operations as an ongoing engineering discipline, rather than a reactive task, tend to achieve the most reliability from their deployments.
The OpenStack Community and Ecosystem
OpenStack is developed and maintained by a global community of contributors, coordinated through the Open Infrastructure Foundation. Contributions come from individuals, universities, and companies that operate or integrate OpenStack in their environments. The software is licensed under the Apache 2.0 license, which allows for free use, modification, and distribution.
The community operates through a governance model that defines technical leadership roles, project teams, and decision-making processes. Development discussions take place in public mailing lists, IRC channels, and virtual meetings. New features and fixes go through a formal review process before being merged into the codebase.
At its peak in the mid 2010s, OpenStack had one of the largest and most active open-source infrastructure communities, with large-scale events such as the OpenStack Summit drawing thousands of attendees. Today, the community is smaller and more specialized. Many early corporate contributors have shifted focus to other technologies, and the remaining participants are often organizations that continue to operate large OpenStack deployments or build commercial products around it.
The surrounding ecosystem includes integration projects and tools for storage, networking, monitoring, and orchestration. Examples include:
- Ceph for distributed storage
- OVN and Open vSwitch for networking
- Prometheus and Grafana for monitoring
- Kubernetes integration via Magnum or custom APIs
- Terraform and Ansible for automation
While the ecosystem is not as broad as it once was, it still supports a range of production use cases, particularly in private cloud, telecom, and research environments. Users who rely on it today often choose it for specific workload needs or for the ability to operate infrastructure fully in-house.