What is a 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 82% of enterprises according to the Cisco 2022 Global Hybrid Cloud Trends Report.
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
cloud work?
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 multi-cloud
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.
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.
Increased flexibility
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:
Compatibility
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.
Increased complexity
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.
Policy management
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.