Combining GCP Stackdriver with a GKE cluster

If you're using GKE cluster, logging is already set up, even though you might not know about it. By default, every GKE cluster comes by default with a Fluentd DaemonSet that is configured to forward logs to GCP Stackdriver. It is running in the kube-system Namespace.

Let's describe GKE's Fluentd DaemonSet and see whether there is any useful information we might find.

 1  kubectl -n kube-system \
 2    describe ds -l k8s-app=fluentd-gcp

The output, limited to the relevant parts, is as follows.

...
Pod Template:
  Labels:     k8s-app=fluentd-gcp
              kubernetes.io/cluster-service=true
              version=v3.1.0
...
  Containers:
   fluentd-gcp:
    Image: gcr.io/stackdriver-agents/stackdriver-logging-agent:0.3-1.5.34-1-k8s-1
    ...

We can see that, among others, the DaemonSet's Pod Template has the label...