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

Chapter 13 ■ Using Autoscaling
Figure 13-8. Listing the pods
We shall invoke the service, which provides an external IP, to put load on the deployment and
test whether varying loads make the autoscaler alter the number of pods proportionately. Obtain the
LoadBalancer Ingress for the service:
./kubectl describe services php-apache | grep "LoadBalancer Ingress"
The public DNS at which the service may be invoked is listed, as shown in Figure 13-9.
Figure 13-9. Obtaining the LoadBalancer Ingress
Invoke the service using the Load Balancer Ingress. An output such as “OK!” is generated as shown
in Figure 13-10; the php-apache deployment is designed only for testing and more elaborate output is not
generated.
Figure 13-10. Invoking the LoadBalancer Ingress
Creating a Horizontal Pod Autoscaler
Next, we shall create a horizontal pod autoscaler for the deployment. An HPA can be created using one of
two available methods:
––
A HorizontalPodAutoscaler object
––
The kubectl autoscale command
The HorizontalPodAutoscaler specification provides the fields shown in Table 13-1.
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