Imagine buying a home. Soon after you purchase, you discover that it has a hidden structural flaw – termite damage, black mold or crumbling clay-tile plumbing. This requires a very expensive fix. In that case, it may have been better to have not purchased the home at all, and instead found a place with fewer issues.
Similar situations can occur with cloud workload placement. In 2019, IDC noted the continued trend of reverse cloud migrations, which involve organizations moving workloads that had previously been placed in the cloud back into on-premises environments, often at great expense.
IDC also estimated that by 2020, 75% of enterprises will also use a private cloud. The reasons include security and compliance, anticipated cost savings that failed to materialize and growing interest in hyper-converged infrastructure. Performing due diligence before a workload goes into the cloud is the best way to avoid the technical complications and potentially high costs of making such adjustments after the fact.
In this article, we’ll look at what steps to consider when deciding where to place a workload, so that you can make an informed choice that will provide the right combination of cloud performance and cost-effectiveness. Let’s go through them one by one, starting with what you need to discover during an initial hybrid IT assessment.
What are the performance characteristics of the workloads in question?
By measuring each workload’s usage of CPU, memory, and networks, it’s possible to get a general sense of whether it would be a good candidate for the cloud.
For example, a highly variable workload such as an intermittently busy e-commerce site or student enrollment system would be ideal for public cloud placement. Because it doesn’t require a steady stream of IT resources, there’s no real reason to purchase and provide them in-house. You would only invest in copious amounts of memory and numerous CPUs that would occasionally be needed at full capacity. Apps with unpredictable demand area are also good cloud candidates for these same reasons.
In contrast, an application that sees constant demand will usually be better suited to legacy/on-prem deployment. Moving it to the cloud could result in major sticker shock, as its level of activity will accrue significant charges for all of the necessary public cloud services, including snapshots and bandwidth.
Does the workload need any modifications before it’s placed in the cloud?
Most of the time, the answer to this question is “yes.” We estimate that at least 80% of workloads require some adjustments before they’re cloud-ready. Sending a legacy workload as-is into a public cloud is typically a recipe for subpar performance and potentially a reverse migration.
Porting an on-prem workload into a cloud-optimized version is a multi-step process, often requiring:
- Applying relevant patches and security upgrades.
- Assessing all of its security contingencies, e.g. with HIPAA, GDPR, etc.
- Identifying the workload’s dependencies on specific pieces of infrastructure.
- Updating or rewriting it for a different OS or framework.
- Placing it into a container for increased portability.
It’s also possible that after performing deeper analysis using versioning tools, you’ll discover that a workload isn’t suitable for a public cloud environment. This could be because of its performance characteristics. Or, because there is a lack of support for its requirements. For example, the decision to port an application to the cloud may not ensure passage of a regulatory audit. The result would require you to know the exact locations of application data and prevent any unauthorized access.
If a workload isn’t cloud-ready or even cloud-suitable, it should be left in place and perhaps revisited later on to see if the situation has changed or if it could be replaced by SaaS.
Would a hybrid cloud that extends the current environment make sense for the workload?
Using multiple clouds is fast becoming the norm. In 2019, RightScale found that most enterprises had a multicloud strategy in place and that the share of businesses combining public and private cloud deployments rose from 51% in 2018 to 58%.
A hybrid cloud can sometimes provide the right balance of control and performance for workloads that are being migrated from a legacy environment. Solutions such as VMware on AWS allow current data center processes and tools to be copied over into a cloud environment.
Moving to this type of hybrid platform requires no sweeping changes. At the same time, it opens the door to additional services for security and disaster recovery. A hybrid cloud ultimately allows for more streamlined data center operations in support of key workflows such as devtest.
What is the business impact of migrating this workload to the cloud?
Without getting into all of the technical details discussed above, a workload’s suitability for the cloud can be evaluated based on how its migration would affect the organization as a whole. For instance, how would it change the day-to-day experience of its end users?
Keeping a workload in a single main data center might actually degrade its performance, due to it being centralized in a location that’s physically quite far from some branch sites. Also, single-site deployments are at higher risk from disasters, since all the eggs are in the same technical basket.
Consider what it would be like to have the bulk of your employees or customers in Seattle while your data center was in New York City. That distance would materially affect workload performance, plus any failure would immediately put you in a bind. The rise of the Internet of Things and the corresponding need to backhaul more data with less latency shows how difficult it will be to maintain certain data center setups going forward.
Shifting more of these sorts of workloads into the cloud might provide some much-needed redundancy and greater geographical distribution. However, there are some different physical limitations that could come into play. A workload that runs on system memory and flash storage in a data center might theoretically be public cloud-able, but it wouldn’t perform exactly the same way once there.
How to make the best decision about workload placement
We’ve covered some of the biggest considerations for placing workloads, but there are others that will inevitably enter the picture. Looking to learn more about the challenges of cloud migration? Check out this Forrester report, 10 Facts Tech Leaders Should Know About Cloud Migration.