Senlin is a new OpenStack project that provides a generic clustering service for OpenStack clouds. It’s capable of managing homogeneous objects exposed by other OpenStack components, including Nova, Heat, or Cinder, making it of interest to anyone using, or thinking of using, VMware Integrated OpenStack.
VMware OpenStack architect Mark Voelker, along with VMware colleague Xinhui Li and Qiming Teng of IBM, offer a helpful introduction to Senlin in their 2016 OpenStack Summit session, now viewable here.
Voelker opens by reviewing the generic requirements for OpenStack clustering, which include simple manageability, expandability on demand, load-balancing, customizability to real-life use cases, and extensibility.
OpenStack already offers limited cluster management capabilities through Heat’s orchestration service, he notes. But Heat’s mission is to orchestrate composite cloud apps using a declarative template format through an OpenStack-native API. While functions like auto-scaling, high availability, and load balancing are complimentary to that mission, having those functions all in a single service isn’t ideal.
“We thought maybe we should think about cluster management as a first class service that everything else could tie into,” Volker recalls, which is where Senlin comes in.
Teng then describes Senlin’s origin, which started as an effort to build within Heat, but soon moved to offload Heat’s autoscaling capabilities into a separate project that expanded OpenStack autoscaling offerings more comprehensively, becoming OpenStack’s first dedicated clustering service.
Senlin is designed to be scalable, load-balanced, highly-available, and manageable, Teng explains, before outlining its server architecture and detailing the operations it supports. “Senlin can manage almost any object,” he says. “It can be another server, a Heat stack, a single volume or floating IP protocol, we don’t care. We wanted to just build a foundational service allowing you to manage any type of resource.”
To end the session, Li offers a demo of how Senlin creates a resilient, auto-scaling cluster with both high availability and load balancing in as little as five minutes.
If you want to learn more about clustering for OpenStack clouds created with VMware Integrated OpenStack (VIO) you can find expert assistance at our product homepage. Also check out our Hands-on Lab, or try VIO for yourself by downloading and installing VMware Integrated OpenStack direct.