Pod Targeting

Pod Targeting allows users to concentrate exclusively on critical pods, while also managing CPU and memory usage effectively.

Processing Traffic Consumes CPU and Memory

Kubeshark’s resource consumption is directly related to the amount of traffic it processes. This becomes a significant issue in busy clusters. Limiting CPU and memory consumption] doesn’t guarantee efficient operation if the allocated resources are insufficient for the traffic volume that Kubeshark needs to handle.

Moreover, the dynamic and distributed architecture of Kubernetes can lead to challenges in tracking and tapping targeted pods, as pods may start and stop, have replicas, and move across nodes.

Consumption Optimization Through Pod Targeting

Pod targeting allows Kubeshark to process traffic from specific pods only, discarding traffic from non-targeted pods.

Kubeshark enables the targeting of specific pods using pod regex (regular expression) and a list of namespaces. It monitors Kubernetes events to track pods that match these criteria across nodes and replicas, tapping into their traffic from launch until termination.

For instance, the following configuration directs Kubeshark to process only traffic associated with pods matching the regex catal.* in the ks-load or sock-shop namespaces:

tap:
  regex: catal.*
  namespaces:
  - ks-load
  - sock-shop

The rest of the traffic will be discarded.

KFL vs. Pod Targeting (Display vs. Capture Filters)

KFL should not be confused with Pod Targeting as they serve different purposes. KFL statements only affect the data presented in the Dashboard, whereas Pod Targeting determines which pods are targeted and, consequently, which traffic is tapped.

For those familiar with Wireshark, KFL can be likened to Wireshark’s Display Filters, and Pod Targeting to Wireshark’s BPF (Berkeley Packet Filter) filters.

Using the Dashboard

You can dynamically set the Pod Targeting properties from the dashboard. To operate the Pod Targeting dialog window, press the kube button located to the right of the Pod Targeting section.

In the dialog window, you can set the namespaces and the pod regex:

The following video demonstrates the behavior:

These Grafana panels show the implications on CPU and memory consumption: