While the public cloud is more high-profile and very popular among developers and testers, the private cloud has an important role to play for businesses with high requirements for security, control and customization. It serves as a landing zone for IT departments that are moving on from legacy systems and/or virtualization projects – once they've started with private cloud storage, compute right and networking, they may add hybrid features or further refine the infrastructure with software such as OpenStack.
Although the private cloud is a starting point for many companies, for others it's an alternative to the unpredictability they've experienced with public resources. Seattle marketing software startup Moz recently shifted a significant portion of its cloud operations away from Amazon Web Services and over to a private cloud to save money. The organization will keep approximately 2,000 servers in the public cloud, but has purchased it own appliances for longer processing.
"For our longer stateful processing or apps that need to be available 24/7 with no variability in load we have purchased our own hardware (a process that has been going on for over 18 months)," stated Moz CTO Anthony Skinner in a post on Hacker News. "Owning the equipment plus the data center will run us [approximately] $1.2 million including growth to build a hot backup."
Moving to a private or public cloud gives enterprises a host of options for combining industry-standard hardware and open source software, resulting in a cost-effective combination that still offers top-flight performance. Moz's example illustrates the appeal of having more control over cloud infrastructure.
At the same time, the private cloud is also a good way to integrate specialized services that run in a secure environment. Writing for EdTech Higher Ed, Alan Joch explained that development and testing was a prominent example of how some workflows can easily be moved into a private cloud, so that resources are more readily available to staff.