adding cni.md (#8760)

* adding cni.md

* apply Zach's feedback

Author: codelearner3012

content/en/docs/reference/glossary/cni.md

@@ -0,0 +1,18 @@
+---
+title: CNI (Container network interface)
+id: cni
+date: 2018-05-25
+full_link: https://kubernetes.io/docs/concepts/extend-kubernetes/compute-storage-net/network-plugins/#cni
+short_description: >
+    Container network interface (CNI) plugins are a type of Network plugin that adheres to the appc/CNI specification.
+
+
+aka: 
+tags:
+- networking 
+---
+ Container network interface (CNI) plugins are a type of Network plugin that adheres to the appc/CNI specification.
+<!--more--> 
+
+* For information on Kubernetes and CNI refer to [this](https://kubernetes.io/docs/concepts/extend-kubernetes/compute-storage-net/network-plugins/#cni).
+* For information on Kubernetes and CNI, see ["Network plugins"](https://kubernetes.io/docs/concepts/extend-kubernetes/compute-storage-net/network-plugins/#cni).