What is hybrid cloud?
Hybrid cloud is a cloud computing architecture that consists of at least one public cloud, at least one private cloud and a hybrid cloud manager (HCM). It is one of the most popular trends in the IT industry, used by 62% of enterprises according to the 451 Research report from 2020.
Hybrid clouds enable organisations to optimise their infrastructure costs by always running their workloads where it makes more sense from an economical standpoint.
How does a hybrid
Since the hybrid cloud is a cloud computing architecture that uses existing public and private cloud infrastructure, the way it works is not significantly different from how public and private clouds work on their own.
The hybrid cloud leverages virtualisation, containerisation, software-defined networking (SDN) and software-defined storage (SDS) technologies to divide physical resources, aggregated into pools, and allocate them to virtual machines (VMs) or containers. Dedicated management software is used to aggregate compute, network and storage resources, distributed across the data centre, and enable on-demand provisioning of virtualised resources through a self-service portal.
What differentiates hybrid cloud from other cloud architectures is the additional layer of software, running on top of existing clouds. Known as the HCM, this software enables deploying, integrating and migrating workloads between private and public clouds depending on capacity and cost conditions. Since private clouds prove to be more cost-effective than public clouds when running workloads in the long term and at scale, the majority of the workloads should always be run in the private cloud. However, organisations can move their workloads to the public cloud during heavy load periods. HCM enables this migration across various cloud providers, ensuring maximum CAPEX and OPEX efficiency.
Hybrid cloud vs
Hybrid cloud and multi-cloud are two mutually exclusive terms that are often confused.
The hybrid cloud is a cloud computing architecture that consists of at least one public cloud, at least one private cloud and the HCM. There are no assumptions in this definition about the service provider behind public and private cloud infrastructure. In turn, multi-cloud simply refers to using multiple clouds from more than one cloud service provider at the same time.
Is every hybrid cloud a multi-cloud?
No, imagine a cloud architecture that consists of AWS and AWS Outposts at the same time. It uses a public cloud and a private cloud infrastructure, but both are delivered by a single cloud provider.
Is every multi-cloud a hybrid cloud?
No, it is not. Multi-cloud also refers to using multiple public clouds (e.g. Azure and GCP) or multiple private clouds (e.g. VMware and OpenStack) at the same time and this is not a hybrid cloud architecture.
Hybrid cloud benefits
The main benefit of the hybrid cloud architecture is better economics compared to using only public or private clouds. Hybrid cloud effectively combines advantages of both, resulting in a number of benefits. Those include:
Maximum infrastructure costs optimisation
In the hybrid cloud workloads always run where it makes the most sense from the economical standpoint. This means organisations always pay as little as possible for the same amount of resources which results in long-term cost savings.
Optimal resource utilisation
Every underutilised resource in the data centre is a waste of money for the business. In the hybrid cloud architecture, the private cloud always runs at its maximum capacity, while workloads are moved to the public cloud during heavy load periods.
Improved agility and scalability
Scaling the private cloud out may take a while due to a long time of the procurement process. Using a hybrid model enables developers to use public cloud resources on-demand until the private cloud grows.
Using more than one cloud environment at a time provides greater flexibility as businesses can choose the right place to run their workloads based on specific use cases and detailed requirements.
Security and compliance
While public clouds are usually considered more secure than private clouds, in some cases having full control over the underlying infrastructure helps organisations to meet their compliance regulations.
Hybrid cloud challenges
While hybrid cloud architecture brings a number of benefits to organisations, implementing the hybrid cloud entails a number of challenges. Those include:
Since various public and private clouds may use different application programming interfaces (APIs) and cloud architectures, managing workloads in the hybrid model is challenging. Using workload management software that is substrate-agnostic helps to bypass those challenges, ensuring compatibility across various cloud providers.
With the hybrid cloud architecture there is no longer a single cloud environment. There are at least two. This increases the complexity of the infrastructure and creates additional overhead for the cloud operations team. One way to deal with that is to leverage managed cloud services.
Due to internal data privacy regulations some data might always have to be stored on-prem. Therefore, implementing hybrid cloud architecture may require introducing a policy management system to make sure confidential data is always secure.
Is hybrid cloud right
Hybrid cloud workloads always run where it makes the most sense from an economical standpoint.
Using this architecture proves to be the best way to achieve infrastructure cost optimisation, however, implementing the hybrid cloud requires building a private cloud which may not be an option due to the significant upfront costs of building a private cloud. Organisations should always carefully analyse their requirements and choose a cloud architecture that provides the best economics. Using private cloud cost calculators can help make the right decision.
Get cost estimates for an enterprise private cloud on Ubuntu ›
Hybrid cloud use cases
Among hundreds of possibilities, typical hybrid cloud use cases include:
Frequently changing workloads
Use “unlimited” resources offered by public cloud providers during heavy load periods, while running the majority of your workloads in a cost-effective private cloud.
Addressing capacity requirements
Use the public cloud as an extension to your private cloud infrastructure until you can scale out the private cloud and meet capacity requirements.
Big data analytics
Use highly-scalable public cloud resources to run your periodic big data analytics, unless you have the capacity to move them to the private cloud.
Moving to the cloud incrementally
Not all workloads are ready for an immediate “lift and shift” migration. Use both clouds at the same time and perform the migration at your own pace.
Ensuring flexibility for the future
Your existing private cloud might not meet your capacity requirements of tomorrow. Using hybrid cloud architecture ensures flexibility for the future as the number of your workloads grow.
Ensuring data sovereignty
Due to internal organisation's regulations, confidential data might always have to be stored on-premises. Using the hybrid model enables you to ensure the sovereignty of your data while running other workloads in the public cloud.
Hybrid cloud architecture
Contrary to public or private clouds, the hybrid cloud rather leverages existing infrastructure components and extends them with an additional layer of the management software that provides workloads orchestration capabilities. In principle, the hybrid cloud consists of the following components:
At least one public cloud
These can be leading public clouds or local ones built to bypass the challenges of hyperscalers that organisations face in some parts of the world.
At least one private cloud
AWS Outposts, Azure Stack, Google Anthos, VMware, Nutanix, CloudStack or the world's leading open source private cloud platform - OpenStack.
Hybrid cloud manager (HCM)
Enables deploying, integrating and migrating workloads between public and private clouds depending on capacity and cost conditions.
In addition, the hybrid cloud leverages a bunch of underpinning technologies, including automation, virtualisation, containerisation, serverless, microservices, etc.
How to build a hybrid cloud?
Building a hybrid cloud usually entails a number of challenges:
These are just a few examples of questions organisations have to ask themselves at the beginning of their hybrid cloud journey. Fortunately, there are tools that enable single-node private cloud installation for testing purposes or, in the case of more complex environments, platform integrators like Canonical offer consulting services for private cloud implementation. Those usually include existing workloads assessment, architecture guidance, TCO prediction, private cloud deployment, workloads migration and hybrid cloud integration.
Get in touch with Canonical for private cloud design and delivery ›
All you need for your hybrid cloud
Charmed OpenStack is a pure upstream OpenStack distribution engineered for the best price-performance with full enterprise support for your production-grade private cloud.
Juju is a Charmed Operator Lifecycle Manager (OLM) that deploys, integrates, and manages Kubernetes, container and VM-native applications seamlessly across hybrid clouds.