scale-from-zero

Test automatic scale from zero

This example shows that NSEs can be created on the fly on NSC requests. This allows effective scaling for endpoints. The requested endpoint will be automatically spawned on the same node as NSC (see step 12), allowing the best performance for connectivity.

Here we are using an endpoint that automatically shuts down when it has no active connection for specified time. We are using very short timeout for the purpose of the test: 15 seconds.

We are only using one client in this test, so removing it (see step 13) will cause the NSE to shut down.

Supplier watches for endpoints it created and clears endpoints that finished their work, thus saving cluster resources (see step 14).

Run

Deploy NSC and supplier:

kubectl apply -k https://github.com/networkservicemesh/deployments-k8s/examples/features/scale-from-zero?ref=407f3cd89a819f104734ff7af542b030bebfe1f8

Wait for applications ready:

kubectl wait -n ns-scale-from-zero --for=condition=ready --timeout=1m pod -l app=nse-supplier-k8s

kubectl wait -n ns-scale-from-zero --for=condition=ready --timeout=1m pod -l app=alpine

kubectl wait -n ns-scale-from-zero --for=condition=ready --timeout=1m pod -l app=nse-icmp-responder

Find NSE pod by label:

NSE=$(kubectl get pod -n ns-scale-from-zero --template '{{range .items}}{{.metadata.name}}{{"\n"}}{{end}}' -l app=nse-icmp-responder)

Check connectivity:

kubectl exec pods/alpine -n ns-scale-from-zero -- ping -c 4 169.254.0.0

kubectl exec $NSE -n ns-scale-from-zero -- ping -c 4 169.254.0.1

Check that the NSE spawned on the same node as NSC:

NSE_NODE=$(kubectl get pod -n ns-scale-from-zero --template '{{range .items}}{{.spec.nodeName}}{{"\n"}}{{end}}' -l app=nse-icmp-responder)
NSC_NODE=$(kubectl get pod -n ns-scale-from-zero --template '{{range .items}}{{.spec.nodeName}}{{"\n"}}{{end}}' -l app=alpine)

if [ $NSC_NODE == $NSE_NODE ]; then echo "OK"; else echo "different nodes"; false; fi

Remove NSC:

kubectl delete pod -n ns-scale-from-zero alpine

Wait for the NSE pod to be deleted:

kubectl wait -n ns-scale-from-zero --for=delete --timeout=1m pod -l app=nse-icmp-responder

Cleanup

Delete namespace:

kubectl delete ns ns-scale-from-zero