BOSTON – Companies that want the security of a private cloud with the elasticity of a public cloud can get both with a hybrid cloud approach, but IT may struggle to manage it.
"When people think about hybrid, it's not one size fits all," said Judith Hurwitz, president and CEO of Hurwitz and Associates, a research firm based in Needham, Massachusetts, during a session here at the Cloud Industry Symposium this week. "Companies need to determine which apps are a good fit for each platform based on security, latency and dependencies."
Enterprises assume building a hybrid cloud will be a mostly seamless transition from their existing cloud environment. However, to have a smooth hybrid cloud rollout, IT must be constantly aware of software updates and must understand that changes that may not impact one area will almost certainly impact another.
For example, dependency, Hurwitz said, is an important issue that is often overlooked in a hybrid cloud deployment.
An enterprise that doesn't factor in its network dependencies before some applications are migrated to a public cloud from on-premises or a private cloud could suffer latency issues. IT shops must also determine their performance needs in the hybrid cloud deployment.
"What we're looking for is, what is the expected wait time?" Hurwitz said. "If I'm using a public or private cloud, is it okay for me to wait two minutes to get a response? What about two seconds?"
That all depends on what you're doing, she said, and isn't black and white. IT must know their cloud provider service-level agreements inside and out and break down applications into well-defined services with standard APIs.
Hybrid cloud deployment obstacles
Deploying a hybrid cloud means making choices about what should reside where and considering cloud performance and security issues.
In the planning stages, IT needs to decide what data should reside in the public cloud versus the private cloud, and whether IT should replicate data across the clouds. Enterprises must know the effect of housing their data in one place versus another.
"Moving jobs between clouds is much easier than moving large amounts of data," said Dan Sullivan, principal of DS Applied Technologies in Portland, Oregon.
"If [an enterprise] replicates data as part of a disaster recovery process they may be able to leverage that data," he said. "Alternatively, they could limit the use of public cloud to compute-intensive jobs with small amounts of data -- but that limits the usefulness of a hybrid cloud."
In this decision, it's important to take performance into account. Ultimately, the enterprise does not consider performance nearly as much as it should, according to David Linthicum, vice president of Cloud Technology Partners in Boston.
Hybrid clouds are network connected distributed workloads, and if the application is not designed properly, it may not perform up to expectations, he said.
Identity management is another consideration, Sullivan said. Companies must ensure employee identities and access controls are the same regardless of where they live in a hybrid cloud.
Managing apps across a hybrid cloud
After a hybrid cloud deployment, the average enterprise will have some applications in the cloud, but some legacy applications may still reside on-premises.
The various locations of applications poses a challenge to IT pros who must monitor and manage each app -- while appeasing CIOs that everything is secure.
The key is to ensure each application lives in its proper place. If an application doesn't perform well on-premises, it might fit better in a public cloud.
"As we think about hybrid, it's not just 'I've got some of this, and some of that,' but how we address app or data integration," Hurwitz said. "'Which one of these many apps is slowing down my environment?'"
The complexity of hybrid cloud management also means considering cloud management platforms.
"Hybrid clouds are complex multi-cloud architectures, thus they need to be managed centrally when in production," Linthicum said.