Kubernetes cluster running with some demo apps.
You can see Cilium and Hubble components running in the kube-system namespace.
kubectl -n kube-system get pods
Pick one of the Cilium pods and you can exec into it, and run both cilium status and hubble status in it
kubectl exec -it -n kube-system cilium-<id> -- cilium status
kubectl exec -it -n kube-system cilium-<id> -- hubble status
This Cilium pod is running on one node, and can see the traffic flowing on that node (only)
kubectl exec -it -n kube-system cilium-<id> -- hubble observe
The Hubble relay combines traffic flows from all the Cilium agents in the cluster.
kubectl exec -it -n kube-system hubble-relay-<id> -- hubble observe
Or you can port-forward the hubble relay to a local port. (Run this in the background, or in a separate terminal)
cilium hubble port-forward
Using an environment variable means we won't have to specify --server localhost:4245 on local hubble CLI commands.
export HUBBLE_SERVER=localhost:4245
Now we can see flows from the whole cluster:
hubble observe
Note that Hubble is showing Kubernetes pod names.