For its 18th code release, issued today, the OpenStack community is making the software easier to deploy on bare metal. The release, named “Rocky,” takes advantage of the way physical servers are managed to make it as fast and easy to deploy OpenStack on physical servers as in virtual machines (VMs).
Jonathan Bryce, executive director with the OpenStack Foundation, said, “We see an environment where people want the right building blocks and to be able to pick a physical server or a VM and have the ability to manage it all in a single platform.”
Many enterprises are starting to deploy containers directly onto bare metal in addition to VMs. OpenStack’s sub-project Ironic is used for provisioning workloads onto bare metal servers — servers that don’t come with a particular operating system pre-loaded. Ironic is one of the fastest growing OpenStack projects.
Bryce said that with the last OpenStack release, Queens, people started to use Ironic in a stand-alone way. “We’ve seen that trend continue to accelerate, driven by GPUs and containerization,” he said.
The Rocky release makes refinements to Ironic, bringing more sophisticated management and automation capabilities so users can manage physical infrastructure in the same way they are used to managing VMs.
Specifically, Rocky provides the ability to manage basic input output system (BIOS) settings. BIOS is the way that a server boots up and manages processors. “When you create a VM, you describe all that in software and it’s all flexible,” said Bryce. “With physical servers you have to have direct physical access to the server to manage those things.” Ironic now lets users manage BIOS settings, bringing bare metal to more use cases.
Rocky also provides an interface in Ironic that gives the ability to boot from RAMdisk, making the experience with physical servers much more similar to working with VMs.
In a world that’s moving to more software, it may seem like back-pedaling to worry about physical servers. But Bryce said, “People like the amount of computing power you get out of a physical server.”
He also said IT environments are moving toward more containers “but most container applications require cloud-native, underlying automation. In some cases they would prefer to run on physical servers and not worry about virtualization in between. That’s been the disconnect between container applications and bare metal servers. The community focused, with Ironic, in bringing those two worlds together.”
Containers in VMs
At VMworld this week, VMware CEO Pat Gelsinger addressed the concern that the company’s virtualization technology may be usurped by containers. Gelsinger said, “Google and all major clouds run their containers in VMs. Simply put, it’s the best way to run containers.”
But the OpenStack community isn’t so convinced.
“We see a couple of different models for containers,” said Bryce. “To date, most containers are running in VMs. In a lot of cases there’s a desire to have higher levels of isolation and security that virtualization can provide.” But he said VMs come with a performance hit. While containers have a small footprint and super-fast startup time, VMs have a larger footprint and slower start-up.
“VMware has a vested interest in people continuing to use virtualization for every workload,” he said. “We see users wanting to diversify the environment they can support. Sometimes bare metal is best, sometimes it’s VMs, and sometimes it’s blended like Kata containers.”
Kata is a container runtime OpenStack launched at the end of 2017. It provides a very small hypervisor that containers can run inside of, so they’re isolated similarly as if in a virtual machine.
Kata is sort of a midpoint between VMs and containers. “Some big public clouds are collaborating on that because they look at scaling out thousands of servers running container workloads, making sure there is an appropriate level of isolation and control,” said Bryce. “They don’t necessarily want to bring in virtualized overhead.”
The Rocky release is also providing users with more flexibility in terms of OpenStack upgrades. “Upgrades have been something that historically have challenged OpenStack users moving from earlier releases to more recent releases,” said Bryce. With Rocky, users can upgrade through multiple releases at one time. This aids operators who don’t want to upgrade every six months, giving more control over the frequency of upgrades.