148422597X Kubernetes Management Design Patterns [Vohra 2017-01-29] {E559F6BB}

Chapter 14 ■ Configuring Logging
• Starting a replication controller
• Starting Fluentd and Elasticsearch to collect logs
• Starting Kibana
Setting the Environment
Create a Kubernetes cluster using a CoreOS-based AWS CloudFormation. List the nodes with kubectl get
nodes. The controller and worker nodes should be listed; we have used a single-controller, three-worker
node cluster as shown in Figure 14-3.
Figure 14-3. Listing Kubernetes nodes
Getting the Logs Generated by Default Logger
The logs generated by a running pod may be obtained with the kubectl logs <POD> command. If a pod has
more than one container, the logs for a particular container may be obtained with the command kubectl
logs <POD> <container>. Kubernetes performs log rotation, and only the latest logs are available to kubectl logs.
First, create a sample pod from which to get the logs. Use the following listing to create a pod definition
file counter-pod.yaml; the pod generates a message using a counter.
---
apiVersion: v1
kind: Pod
metadata:
name: counter
spec:
containers:
-
args:
- bash
- "-c"
- "for ((i = 0; ; i++)); do echo \"$i: $(date)\"; sleep 1; done"
image: "ubuntu:14.04"
name: count
The pod definition file is shown in the vi editor in Figure 14-4.
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