Containers are back! This old technology is becoming new again as companies are pairing it with virtualization to run multiple isolated systems through one host.
James Bottomley, CTO of virtualization technology at Parallels, told me that containers came onto the scene about 25 year ago, used with old BSD operating systems that contain “service demons,” like BSD jails.
How containers are being used now is that while virtualization is a big thing going on, the main problem is that it is not easy to see what is going on — there are lots of tricks at the nest level, Bottomley said. With containers, it uses the same kernel, so it naturally occurs easier, he said.
Last year, Steven J. Vaughan-Nichols wrote in ITworld that Linux and Docker were taking containers mainstream, which meant big changes to the cloud as well as server farms and data centers.
Cisco also posted an article that said “Linux containers and Docker are poised to radically change the way applications are built, shipped, deployed, and instantiated. They accelerate application delivery by making it easy to package applications along with their dependencies. As a result, the same containerized application can operate in different development, test, and production environments.”
Some have also touted containers’ ability to solve virtualization issues. David Egts wrote that containers may be able to solve some problems as the U.S. Department of Defense started virtualizing its systems.
Bottomley said containers are very suited for working with the cloud, but are still a technology that people have heard of yet don’t understand.
One solution, early on, had been to use containers to bring up applications inside hypervisors, but developers found that problems arose when they tried to do things like scaling, Bottomley said.
He said Google uses containers all the time for its different applications like Gmail, which enable it to scale up or down depending on the need.
So when Parallels was able to find a new use for containers, that is when the company first started to get excited, he said.
And that is using containers with cloud server virtualization, which enable users to make modifications to the hosting environment and cloud server while still getting maximum density, cost efficiency, and performance of applications.
What Parallels is doing is different from what Docker is doing, Bottomley said. Parallels is supplying containers, while Docker lets users create a containerized application and deploy it to the cloud.
Whatever comes about with this technology, Bottomley thinks 2015 will the year that we see a new crop of uses come online for containers.
Photo credit: Håkan Dahlström via Flickr