Cumulus Networks makes a standalone network OS (NOS) called Cumulus Linux that’s designed to be loaded onto white box switches. But recently the company announced Cumulus Express, a new program in which it will sell switch hardware with its NOS pre-installed.
For a company that came to market touting the benefits of disaggregation (that is, separating the NOS from the hardware), and which has partnered with numerous hardware vendors to sell its software, the announcement came as something of a surprise. Why would the startup take a step toward re-aggregation?
The answer, according to CEO Josh Leslie, is customers. “We’re trying to figure out how to get customers to be successful quickly and easily,” he said in an interview. In other words, sell them a box (or a lot of boxes) with the OS already installed so they can get up and running faster.
He noted that the benefits of disaggregation, such as the ability to get hardware vendors to compete, and to enjoy underlying improvements in hardware without having to change your software stack, are downstream benefits, or benefits that show up at scale.
The most immediate value, according to Leslie, comes from the software, such as having control over the software stack and being able to operate and manage the network using Linux-based tools.
When Is A Hardware Vendor Not A Hardware Vendor?
The Cumulus Express line is built on hardware from EdgeCore, with port speeds ranging from 1Gbps to 100Gbps. These products were already on Cumulus’s hardware compatibility list.
Cumulus will act as the seller of record and provide support for both software and hardware on the Express line.
At the same time, CEO Leslie says “We don’t see ourselves as getting in the hardware business.”
That’s an odd statement for an organization that just announced it’s selling metal boxes. I think it’s an indication of the fine line that Cumulus is trying to walk both as an organization, and as a partner with hardware suppliers such as Dell and Mellanox.
Organizationally, the company has to be careful with taking on the costs that come with selling hardware. In addition to product support, the company has to deal with inventory management, shipping, hardware licensing, and supply chain issues. Leslie said Cumulus has partnered with a distribution company to help with the physical side of this business.
“We’ve tried to figure out the back end in a way that’s simple for our company,” said Leslie. He also noted that Cumulus didn’t have to take on additional funding to spin up the hardware side of the business, nor does he anticipate tying up capital in hardware.
As for partners, Leslie was careful to note that it isn’t trying to crowd out other hardware providers.
“We aren’t competing with our partners,” he said. “The Dell relationship has been good to us, we have a lot of joint customers and we are committed to working with them.”
He also noted that the startup put a significant amount of time and investment into porting Cumulus onto Mellanox’s silicon, so it isn’t out to endanger that relationship.
Mellanox has “great technology and it’s well aligned. We have a software stack and they have a hardware offering, so the combination of those products will be very good.”
However, he notes that not all of Cumulus’s customers buy from its partners, so the startup wants to accommodate those buyers.
I asked about Cumulus and Barefoot Networks. Barefoot has released a programmable switch ASIC, called Tofino, and will have hardware partners shipping Tofino-based switches in early 2017. However, Barefoot hasn’t announced any official support for network OSs, and Cumulus seemed to me a logical candidate.
Leslie said the Cumulus technical team is very interested in Barefoot, but the company has no firm plans to work with the Tofino chip.
To my ears, it sounds like this decision is driven by customer demand—or lack of it.
“We have to be thoughtful about the order in which we do these things,” said Leslie. “If it cost us nothing, we would’ve done it yesterday. But every decision to work with a vendor consumes varying degrees of resources for the company. So we have to make sure we can deliver the most value to our customers and not get distracted because something is cool.”
New Support For Facebook Designs
Cumulus Networks also announced that its NOS can now run on two switch platforms driven by Facebook and the Open Compute Project. Cumulus supports Backpack, an 8RU switch chassis with 128 100Gbps ports, and the Wedge 100, a fixed configuration switch.
The Backpack chassis with the Cumulus NOS is available for pre-order now.