Netscaler CPX Express, a developer version of the CPX container, is available for free downloading, the company announced yesterday at LinuxCon North America in Toronto. There’s even a catchy URL for it: microloadbalancer.com
Revealed earlier this year, CPX is a container version of Netscaler’s application delivery controller (ADC). CPX Express does the same thing but in a sample size. It handles only 20 Mb/s of traffic, whereas the commercial CPX offering supports 1 Gb/s. CPX Express is also missing TCP optimization and Level 7 distributed denial-of-service protection.
Other open source load balancers exist, such as Zen or nginx (the latter is an HTTP proxy server that’s usable as a load balancer). Both arose before the concept of microservices took hold in the industry’s collective brain, though. Citrix is claiming CPX Express is the first free load balancer designed with microservices in mind.
In his LinuxCon keynote, Abhishek Chauhan, Citrix’s CTO of delivery networks, described microservices as a decoupling of software into components — the same kind of disaggregation behind software-defined networking (SDN) or composable infrastructure.
This separation opens possibilities for some new functions, such as client-directed load balancing, or per-host or per-service network functions, Chauhan said.
But the disaggregated pieces of software need to connect to one another, leading to a point that Chauhan admitted was “obvious,” namely: “Now you also expect the network to be small, composable, and disaggregated.” Naturally, CPX Express is an example of that kind of new network element.
Network disaggregation does open up new challenges, particularly when it comes to network management. If the data plane splinters into tens of thousands — possibly hundreds of thousands — of containers, “you need something that will take all that distributed state and be the caretaker,” Chauhan said.
The other challenge facing enterprise IT is that it’s going to have to support multiple platforms. Chauhan said he’s encountering more enterprises supporting all manner of options: containers, virtual machines, public clouds, and on-premises equipment. This is partly because the new DevOps-minded infrastructure (containers and public cloud) doesn’t necessarily fit for older applications. What’s needed is a way for enterprises to make this transition gradually.
“They see all the shiny new objects we show them,” Chauhan said. “The way they are going to adopt them is through a bridge from what they have today.”