VMware shops can have their cake and eat it, too.
IT pros see VMware's recent release of its own Linux-based operating system as a way to dovetail application containers into existing VMware tools, if other container OS options don't win out.
Early users of Photon OS aren't applying it to production workloads yet, but they see it as a way to eventually connect application containers to the data center infrastructure.
Project Photon provides a VMware-branded Linux distribution to support applications and containers in a VMware-centric environment. Part of that is Photon OS, a Linux OS released out of beta earlier this month that is embedded in both vSphere Integrated Containers and the Photon Platform. It is a kernel purpose-built and optimized for containers, and it is not a general-purpose Linux distribution, said Brad Meiseles, senior director of engineering for cloud-native apps at VMware.
Philip Buckley-Mellor, a designer at BT TV, part of the BT Group PLC in London, has used Photon OS in a test and development environment since last year and is "very impressed with it so far." He said he thinks more components are needed for a complete VMware environment, "but we know that is in flight at the moment."
In part, container management system Project Lightwave will address some of its needs, he said.
Developers at BT TV have pushed to use more modern technologies beyond pure VMs, including containers, Buckley-Mellor said.
If Photon OS can help him feel as comfortable with containers as he is with VMs, he said he will use containers.
"We're getting to a point where we think we can securely deploy containers where we think it does not break our current support model," he said. "We are not there yet, but this is a very major milestone."
Docker was on the radar for Umbrellar Cloud Hosting in Auckland, New Zealand, but without a use case, the company hadn't put a lot of time into investigating it, said Darran Provis, senior system administrator.
When some larger customers began to use Docker and asked Umbrellar to host their test and development servers, the company sought out the best way to do it and found Photon OS, which seemed like it would play nicely with its VMware environment, Provis said.
A few Umbrellar customers use Photon OS as a standard Docker host, with the Docker containers running on the Photon host directly. "We could simply deploy a standard Linux VM with Docker installed, but we wanted to test Photon in a semiproduction environment," he said.
The first production cut of vSphere Integrated Containers will make Photon OS more useful in his environment, since Photon OS by itself is no different than a Docker install on a minimal Linux distribution, Provis said.
Darran Provissenior system administrator, Umbrellar Cloud Hosting
"We quickly realized Photon OS is only the tip of the iceberg of what we could use for auto-deployment of full Docker container environments," he said. "Using Photon OS with other [VMware] products will show its true power."
Integration with existing VMware environments could be the "ace up its sleeve" for Photon OS, said Stuart Burns, a virtualization and Linux expert at a Fortune 500 company, and TechTarget contributor.
When the full Docker platform and management services are available from VMware, the interface will look similar to the current platform -- instead of seeing VMs, you will see Docker instances, "but the familiarity will be there," he said.
A standard VM can take several hours to get running in a large environment, taking into account the build, quality assurance and documentation all done by different teams. By comparison, for a Docker host, an administrator can pull an image and be up and running in seconds, Burns said.
"It really cuts down the time to delivery for applications and, in essence, passes a lot of the deployment management to the developers and an automation system," he said.
Containers don't completely replace VMs -- VMware's bread and butter for years -- but can replace them in some instances and also work well together, said Gary Chen, analysis at IDC.
Both Chen and Provis agreed the open source nature of Photon OS -- available on GitHub -- likely will get a push from the open source community to move it forward much faster than full VMware in-house development. Provis said he sees vast potential in the Photon OS project, and the business model for Photon OS and vSphere Integrated Containers will still require licensing fees in order to use some features.
"VMware is taking the smart road of mixing open source with licensed products," Provis said.
Photon OS is one of many Docker host platforms alongside CoreOS and RancherOS, but it has the advantage of being from the "800-pound King Kong of the traditional virtual world," Burns said.
Buckley-Mellor also uses Oracle Enterprise Linux, and said he thinks Red Hat and Oracle both take containers seriously and are making progress in that area.
Robert Gates covers data centers, data center strategies, server technologies, converged and hyper-converged infrastructure and open source operating systems for SearchDataCenter. Follow him on Twitter @RBGatesTT or email him at firstname.lastname@example.org.
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