One can be forgiven for thinking that everything about computers is absorbed in the cloud. There is immense pressure to move the cloud. As a recent IDG survey of 550 senior executives reveals, over one-third (38%) say their IT departments are under pressure to migrate all applications and infrastructure to the cloud.

Photo: Joe McKendrick

However, it should be noted that at this point, most IT and enterprise data assets are still in their own data centers. Some applications and systems are simply not suitable for the cloud at the moment – and may never be integrated into the cloud. How do IT decision makers determine when a migration to the cloud does not make sense and that it's best to leave things on-site? Previous IDG polls found that 56 percent of executives plan to keep their systems on-premise in the near future, and at least 40 percent say they are too dependent on legacy systems to migrate to the cloud.

To explore the issues of staying on site rather than on the cloud, I've been interviewing industry leaders on areas that were unsuitable for the cloud and that were best left on site – especially from the point of view of the cloud. view of very important data. The implications for security, as well as the requirements of geographical presence, are obvious. But there are also other facts that can make staying on the spot the most viable option. Here are some of the concerns raised:

Legacy entanglements: For starters, there can be a very complex tangle of on-site assets making moving a particular item to the cloud a complicated project, says Hal Woods, director of technology at Datera. "If a given application interacts strongly with other applications that need to run on-site, this application and its database must also run naturally, on-site," he said.

Aboy Radhakrishnan, CTO architect for Sungard Availability Services, agrees: "Applications that integrate with the database and are set up with a runtime environment or a particular server for basic versions specific data "are preferable on site. In addition, he also saw examples of on-premise applications that "are adapted to specific versions of their databases on certain platforms for reasons of performance and reliability."

Traditional monolithic applications can also be simply a bear to migrate. "Existing applications and applications with monolithic database structures are always better suited for on-premise applications," said Scott Harvey, vice president of engineering and operations at Atmosera. "In general, existing applications are not compatible with the cloud, especially with some of the abstractions in the public cloud, such as SaaS or PaaS offerings, which remove some of the more management-centric configurations and management features. System administrator, or, in the case of PaaS offers, not offering parity with on-site installations of database engines. "

Shock cloud sticker: Increasing cloud costs is another case of keeping some assets on site. Datera's Woods reports that "some public cloud providers are known to ingest data at a reasonable cost, but they are very expensive.After receiving a huge bill, many companies plan to recover some of their databases. on site, as was the case with one of our customers. "

Security: The data itself can be complicated, and this makes cloud movements untenable, "says Dave Nielsen, Redis Labs Ecosystem Program Manager. "Some data may be exposed publicly, and some data may not risk even a hint of exposure.In this second case, a ventilated on-site system may offer better security."

Need of speed: There could also be a need for speed, adds Nielsen. "Large data collections can take hours or even days to move from a data center to the cloud – applications that manage large data on-premises must be located near the data, so that They can better interact with data – modern applications that rely on real-time interaction of user data, quick analysis, customization or recommendation. "This can also be extended to the user's configurations. Internet of things. "If you collect data at a high rate from local IoT devices, the direct transition to a public cloud may be too slow, so it makes more sense to use a database." local or cloud edge, "says Woods.

Nevertheless, some companies opt for everything in the cloud, especially those that do not have inventories of computer systems already elaborated and carefully configured to respond to their particular situations. "We're seeing it primarily in start-ups and innovative divisions of companies that work with big data, streaming data, data analytics applications, and new cutting-edge technologies like artificial intelligence, machine learning and blockchain, "says Radhakrishnan. "Companies that are turning more towards cloud computing are generally those in sectors subject to less stringent regulations, such as entertainment, media, travel or logistics."

While Atmosera still presents Harvey's largest, leading-edge applications requiring high-performance, onsite databases, the cloud is ideal for "less demanding applications." Going to the cloud "has the advantage of being faster for a business because it allows you to instantly increase and reduce the amount of material to scale, instead of ordering and to install equipment on site, "he says. "While earlier investments in onsite hardware are typically used, other factors, including the administrative burden of infrastructure, can make a business move to a public cloud sooner than ever before."