What Is Layer-2 and Why Do We Need It?
I’m constantly ranting against large layer-2 domains; recently going as far as saying “we don’t really need all that stuff.” Unfortunately, the IP+Ethernet mentality is so deeply ingrained in every networking engineer’s mind that we rarely ever stop to question its validity.
Let’s fix that and start with the fundamental question: What is Layer-2?
Read more ...Big Tap sFlow: Enabling Pervasive Flow-level Visibility
Today's Big Switch Networks webinar, Big Tap sFlow: Enabling Pervasive Flow-level Visibility, describes how Big Switch uses software defined networking (SDN) to control commodity switches and deliver network visibility. The webinar presents a live demonstration showing how real-time sFlow analytics is used to automatically drive SDN actions to provide a "smarter way to find a needle in a haystack."
The video presentation covers the following topics:
- 0:00 Introduction to Big Tap
- 7:00 sFlow generation and use cases
- 12:30 Demonstration of real-time tap triggering based on sFlow
The webinar describes how the network wide monitoring provided by industry standard sFlow instrumentation complements the Big Tap SDN controller's ability to capture and direct packet selected packet streams to visibility tools.
The above slide from the webinar draws an analogy for the role that sFlow plays in targeting the capture network to that of a finderscope, the small, wide-angle telescope used to provide an overview of the sky and guide the telescope to its target. Support for the sFlow measurement standard is built into commodity switch hardware and is enabled on all ports in the capture network to provide a wide angle view of all traffic in the data center. Once Continue reading
Logging in Kubernetes with Fluentd and Elasticsearch
In previous posts, we talked about running skyDNS and Heapster on your Kubernetes cluster. In this post, I want to talk about the last of the cluster ‘addons’ available today in the Kubernetes repository. This add on is a combination of Fluentd, Elasticsearch, and Kibana that makes a pretty powerful logging aggregation system on top of your Kubernetes cluster. One of the major struggles with any large deployment is logging. Having a central place to aggregate logs makes troubleshooting and analysis considerably easier to do. That being said, let’s jump right into the configuration.
Note: I have an open PR on this addon to make it a little more flexible from a configuration perspective. Namely, I want to be able to specify the port and protocol used by the API server to access the backend service when using the API server as a service proxy. That being said, some of my pod/controller definitions will be different from what you see on GitHub. I’ll point out the differences below when we come across them.
The first step is to have the Kubernetes nodes collect the logs. This is done with a local Fluentd Continue reading
Juniper & VMware Back Off from OpenDaylight
Both companies appear ready to ratchet down their participation in the open source project.