Hybrid clouds – the concept of maintaining workloads across different IaaS providers and on-premises is increasingly the preferred approach for IT organizations across the globe today. Just like a multi-vendor approach to selecting Networking equipment is the preferred method, a multi-cloud architecture is advocated. The principles of some of these pros are enshrined by the IaaS providers themselves. Here are some:
- Redundancy Easily the most prominent gain in a movement to public cloud. All IaaS providers advocate a multi-region, multi-zone deployment to ensure High Availability and enable Fault Tolerance. They do provide an easy to implement redundancy solution in their cloud environments. For IT departments that need to safeguard the interests of their users and customers, redundancy always scores high in the list of priorities to consider during the deployment of a data center or migration of workloads. While the is redundancy in the cloud is made easy by the cloud service providers, organizations need to be smart about implementing redundancy of the cloud (IaaS providers). One always needs to guard against the failure or collapse of any of the IaaS providers for any number of reasons. Therefore, deploying the applications/ workloads/ data center with more than one cloud service provider is important.
- Cost Optimizing costs will also dictate that one leverages the different cost structures of the IaaS providers. Intelligently deciding on a mapping of the workload to the most efficient provider based on the usage parameters is crucial. For example, a use case that is receiving streaming data that sees a large number of writes per second to the database is completely different from a web-server application that has seasonal peaks in reads and occasional writes. Cost implications will differ similarly.
- Independence The last thing any CIO needs is to be dependent on the strategies and changes from a single IaaS provider. Just when all the time and effort has been spent on migrating workloads to a Cloud service provider, if the vendor chooses to change their offer or increase their price, it makes all the planning and costs estimates go awry. Or if there are issues encountered, one would be at the mercy of the single vendor with no way out. Multiple vendors allow for strength in bargaining and in implementation.
Every ying has its yang. What are the challenges with a multi-cloud approach?
- Training Each IaaS provider has implemented their own version of a Virtual Private Cloud (VPC), Resource groups and Networking concepts. There is no standardized approach available, nor is it likely to be framed anytime soon. This means that personnel deploying, managing and administering the workloads across these clouds need to be trained in the nuances of each of them. This is hard, not just in terms of the training overhead, but also for the Engineers who have to remember the various options available in each IaaS provider.
- Automation It is a given that all deployments and configurations must be automated. With multiple clouds and each supporting their own automation framework, the task becomes that much more difficult. Of course, Terraform does address the issue to some extent, but there is no way that any automation framework that abstracts the AWS, Azure and Google frameworks can keep up with the pace of development and versioning of the proprietary APIs.
- Security 3rd in the list, but (hopefully) topmost in the minds of CIOs and CISOs. How does one implement consistent security policies from on-premises equipment to the cloud? How can it be ensured that the data is encrypted at rest and in-transit, with algorithms that are (preferably) consistent across the multi-cloud for ease of manageability? Ensuring security without impacting user experience is an immense challenge and there are so many vendors that provide solutions that cater to different requirements. How do you choose one that understands your specific use case and actually has an open solution that, again, inter-operates with other security vendor solutions? The choices are plenty and compromised security is not something that anyone wants to deal with. Architectures that ensure security is at the heart of every design principle and implementation are needed.
Philosophically, every idea has its pros and cons and so it is with a migration to a hybrid cloud architecture. It is also true that as enterprises implement their “Cloud First” initiatives, the attractiveness and pragmatism of a multi-cloud architecture outweigh the risks of a single vendor or single cloud solution. It is impossible to say how many or which IaaS providers will be around 10-15 years from now. The safest bet is to explore the top 3 in the world at the moment, viz. Amazon’s AWS, Microsoft’s Azure and Google’s GCP. Your thoughts?