network-mapper VS tic-tac-toe

Yep! When you deploy Otterize, you get a map of your cluster’s traffic, with zero-configuration, through the open-source network-mapper.

After multiple iterations, research sessions and some trial & error, we could produce an exportable list of network connections in any Kubernetes cluster. You might recall that our larger goal was to get to a logical (functional) map of pod-to-pod traffic, and that will be covered in a future posting. After adding that capability, here’s an example output from our project, now called network-mapper, when pointed at one of the clusters in our “lab” environment:

It'll require some changes but you can go for it if that's something up your alley, as after all, it's all open source - https://github.com/otterize/network-mapper

We received some great feedback from the community regarding our tool, and one of the most commonly requested features was visualization. So we embedded this functionality into the tool, and now you can easily map and visualize your cluster with a single CLI command.

As you've mentioned, it is not possible to define deny rules using the native NetworkPolicy resource. Instead, you could use your CNI’s implementation for network policies. If you use Calico as your CNI you can use Calico's network policies to create deny rules. You can also take a look at Otterize OSS, an open-source solution my team and I are working on recently. It simplifies network policies by defining them from the client’s perspective in a ClientIntents resource. You can use the network mapper to auto-generate those ClientIntents from the traffic in your cluster, and then deploy them and let the intents-operator manage the network policies for you.