Overlay networking
By default, CDW uses CNI overlay networking.
Default CDW networking
Using Azure Container Networking Interface (CNI), every
pod gets an IP address from the node subnet and is accessed directly. Each IP address must
be unique across your network space, and you must plan for them in advance of deploying your
CDW cluster. Each node has a configuration parameter for the maximum number of pods that it
can support. The equivalent number of IP addresses per executor node is reserved up front
for it. This requires advanced planning and it can often lead to IP address exhaustion. As
an alternative, you must rebuild the cluster in large subnets so your cluster can meet your
applications' demands. You can configure the maximum pods that are deployable to an executor
node when you create the cluster or when you create new executor node pools. However, if you
do not specify the maximum number of pods for the maxPods
property when you
create new executor node pools, by default each executor node gets 30 pods (with one IP
address per pod).
About using overlay networking
To avoid IP address exhaustion, you can enable the overlay networking feature when you activate an Azure environment to use with CDW. For a full description of CNI Overlay networking in AKS, see the Microsoft documentation.