Hybrid cloud strategy is a how organizations determine which applications and data should reside on which parts of a hybrid cloud infrastructure. Simply, hybrid cloud strategy defines what goes on public cloud infrastructure, and what goes on private cloud infrastructure.
Although definitions of hybrid cloud architecture vary widely, there are two defining components: Public cloud infrastructure (typically infrastructure as a service or IaaS), and private cloud infrastructure, such as an on-premises data center that may or may not utilize a cloud platform.
Enterprises are increasingly embracing public cloud services as part of their overall IT strategy, evidenced by the McAfee's 2019 Cloud Adoption and Risk Report, indicating that the average organization employed an average of 1,935 cloud services
From a higher viewpoint, a hybrid cloud strategy brings together private cloud and one or more public cloud providers, who can share and migrate applications and data over a wide area network (WAN) connection.
One of the primary uses of a hybrid cloud is for disaster recovery and business continuity (DR/BC), where enterprise data and snapshots are stored in the public cloud for rapid recovery. Another popular strategy is cloudbursting – utilizing public cloud services when spikes in demand require additional computing power for applications during periods of high usage, thus eliminating the need to over-provision equipment that would be only rarely utilized.
Before developing a strategy for hybrid cloud computing, enterprises must assess existing applications, both legacy and modern, to determine whether each might be a candidate for operating in a public cloud environment. Considerations should include security, regulatory, compliance, and data governance demands, cost of virtual machine (VM) subscriptions versus the amortized costs of on-premises infrastructure, and technology advantages of candidate cloud providers, including ease of integration between hosted and on-premises applications and data.
Hybrid cloud strategy encompasses seamless workload portability between private and public clouds, and should be based on a common, consistent cloud architecture that spans both public and private, simplifying orchestration between both, such as VMware orchestration tools for VMs and Kubernetes for containerized applications.
Those enterprises that adopt standard architecture encompassing public and private clouds will find the migration to a hybrid cloud environment greatly simplified. Of course some applications are more portable than others, migrating a web front-end application to the cloud is much easier than moving a heavily used database, and once moved into the cloud many cloud service providers (CSPs) impose egress charges on data that is taken off the cloud for processing elsewhere – these charges can add up quickly and generate quarterly invoice sticker shock.
Accenture offers a ‘seven Rs’ methodology for determining a hybrid cloud strategy which encompasses:
There are some challenges to navigate when developing a hybrid cloud strategy. Organizations should start with a complete and thorough assessment of existing applications and data to uncover risks and expose hidden value to the enterprise.
Multiple cloud challenges
Many hybrid cloud environment involve multiple public cloud provider, and all hybrid clouds by definition have both public and private clouds. It can be challenging to determine which application is best suited to which cloud and determining the true cost of operation of an application in the public cloud versus running that application on-premises may not be apparent until the application has been rehosted and ‘hidden’ charges become apparent.
As with any environment where there are multiple environments, there is always the opportunity for finger-pointing when deployments do not proceed exactly as planned. Determining the root cause of problems in a hybrid cloud environment requires the commitment for close collaboration between on-premises private cloud team and one or more public cloud teams.
Cloud cost confusion
Integrating public and private cloud operations can involve unimagined costs for additional software licenses, charges for VMs that are not being utilized, and data egress charges to name just a few. When planning a hybrid cloud strategy enterprises should architect data flows and application utilization to minimize CSP costs while maximizing performance and overall cost efficiency.
Scalability is a prime reason for adopting a hybrid strategy, and yet it can also present difficulties if attempting to scale private cloud applications that are isolated by on-premises firewalls. When planning for cloud bursting to the public cloud ensure the applications are architected to access public cloud resources when needed.
No magic bullets
Organizations must find the right tools and platforms to facilitate a hybrid cloud strategy. In most cases where will be multiple tools, multiple integrations, and multiple vendors involved, both in the public cloud and for on-premises infrastructure. Choose the right tools for each use case rather than trying to shoehorn every application into the same tool set.
Global technology firm Cloudnexion published research that outlines the five top benefits of adopting a hybrid cloud strategy, here are their findings.