What do 3,000 or so Ubuntu server and cloud users have to say about the cloud that you might care about? A lot. Besides having its own cloud offering, Ubuntu OpenStack, Ubuntu is the most popular operating system by more than two to one on the Amazon Elastic Compute Cloud (EC2). In other words, Ubuntu cloud users know what they're talking about when they talk cloud.

In Canonical's sixth annual Ubuntu Server and Cloud Survey, the company found -- no surprise -- that the enterprise is rapidly adopting the cloud. Further, the cloud is moving from "mostly development and testing to more production-grade workloads".

What kind of cloud? It's still heavily weighted to private clouds, which has 35 percent of users. The most popular platform for private cloud is OpenStack, which is used by 53 percent of users. At the same time, hybrid clouds are on the rise, at 20 percent, up from 15 percent last year. Indeed, the survey found that hybrid clouds are now almost as popular as public cloud, which is at 23 percent.

Interestingly, public cloud usage, which scored 27 percent in 2013, is declining, despite all the many recent price cuts by major public cloud providers. This leads to the conclusion that saving money alone is not the reason why companies are adopting clouds.

Canonical speculated, "Hybrid is clearly an appealing strategy for enterprises, because it offers the balance of economic and technical benefits of the public cloud with the control and security of a private cloud."

As GigaOm Research analyst David Linthicum recently observed, "Most enterprises are moving toward hybrid and multi-cloud computing. In some cases, there is a clear business case. At other times, it just seems like hybrid is the approach that gives an enterprise the most options and the most control."

It may also be because enterprises don't fully trust public clouds. The Ubuntu Cloud Survey found that security and privacy remained, with 34 percent, the top barrier to cloud adoption.

Whatever kind of cloud an organization adopts, Canonical discovered that there is a continued shift to running more mission-critical programs on the cloud. More than 75 percent of users are deploying workloads like big data, analytics, CRM, scientific apps, and virtualization on clouds. Last year, it was only 64 percent.

In other words, companies are not simply replacing datacenter servers with clouds; they're moving the new applications to the cloud. For instance, two thirds of the surveyed "OpenStack users are deploying mission-critical functions to it, while nearly half are deploying infrastructure and virtualized environments".

Indeed, the survey also revealed the three major trends driving cloud adoption: Connected devices/Internet of Things (33 percent), growing data volumes, and the software-defined datacenter (26 percent each). The first two are intimately connected, as the increase in connected devices is generating more data than ever, necessitating the use of increasingly scalable and flexible storage and compute platforms -- the cloud -- to store and process this data.

At the same time, while developers love Docker, the container technology, it's still a "new kid on the block" when it comes to adoption. Most Ubuntu Docker users are still just trying it out for development and testing rather than rushing it into production.

Finally, Ubuntu users are also very interested in becoming OpenStack users. They may run Ubuntu on Amazon or the Google Compute Engine, but 64 percent think OpenStack is already ready for mission-critical workloads.

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