iPerf

Perform real-time network throughput measurements while using iPerf3

This example is part of a suite of examples showing the different ways you can use Skupper to connect services across cloud providers, data centers, and edge sites.

Contents

• Overview
• Prerequisites
• Step 1: Access your Kubernetes clusters
• Step 2: Create your Kubernetes namespaces
• Step 3: Install Skupper on your Kubernetes clusters
• Step 4: Install the Skupper command-line tool
• Step 5: Create your sites
• Step 6: Link your sites
• Step 7: Deploy the iperf3 servers
• Step 8: Create connectors for the iperf3 servers
• Step 9: Create listeners for the iperf3 services
• Step 10: Run benchmark tests across the clusters
• Cleaning up
• Next steps
• About this example

Overview

This tutorial demonstrates how to perform real-time network throughput measurements across Kubernetes using the iperf3 tool. In this tutorial you:

• deploy iperf3 in two separate clusters
• run iperf3 client test instances

Prerequisites

• The kubectl command-line tool, version 1.15 or later ([installation guide][install-kubectl])

• Access to two clusters to observe performance. As an example, the two clusters might consist of:

• A private cloud cluster running on your local machine (east)

• A public cloud cluster running in a public cloud provider (west)

Step 1: Access your Kubernetes clusters

Skupper is designed for use with multiple Kubernetes clusters. The skupper and kubectl commands use your kubeconfig and current context to select the cluster and namespace where they operate.

This example uses multiple cluster contexts at once. The KUBECONFIG environment variable tells skupper and kubectl which kubeconfig to use.

For each cluster, open a new terminal window. In each terminal, set the KUBECONFIG environment variable to a different path and log in to your cluster.

West:

export KUBECONFIG=~/.kube/config-west
<provider-specific login command>

East:

export KUBECONFIG=~/.kube/config-east
<provider-specific login command>

Note: The login procedure varies by provider.

Step 2: Create your Kubernetes namespaces

The example application has different components deployed to different Kubernetes namespaces. To set up our example, we need to create the namespaces.

For each cluster, use kubectl create namespace and kubectl config set-context to create the namespace you wish to use and set the namespace on your current context.

West:

kubectl create namespace west
kubectl config set-context --current --namespace west

East:

kubectl create namespace east
kubectl config set-context --current --namespace east

Step 3: Install Skupper on your Kubernetes clusters

Using Skupper on Kubernetes requires the installation of the Skupper custom resource definitions (CRDs) and the Skupper controller.

For each cluster, use kubectl apply with the Skupper installation YAML to install the CRDs and controller.

West:

kubectl apply -f https://skupper.io/v2/install.yaml

East:

kubectl apply -f https://skupper.io/v2/install.yaml

Step 4: Install the Skupper command-line tool

This example uses the Skupper command-line tool to create Skupper resources. You need to install the skupper command only once for each development environment.

On Linux or Mac, you can use the install script (inspect it here) to download and extract the command:

curl https://skupper.io/v2/install.sh | sh

The script installs the command under your home directory. It prompts you to add the command to your path if necessary.

For Windows and other installation options, see Installing Skupper.

Step 5: Create your sites

A Skupper site is a location where your application workloads are running. Sites are linked together to form a network for your application.

For each namespace, use skupper site create with a site name of your choice. This creates the site resource and deploys the Skupper router to the namespace.

Note: If you are using Minikube, you need to start minikube tunnel before you run skupper site create.

West:

skupper site create west --enable-link-access

Sample output:

$ skupper site create west --enable-link-access
Waiting for status...
Site "west" is configured. Check the status to see when it is ready

East:

skupper site create east --enable-link-access

Sample output:

$ skupper site create east --enable-link-access
Waiting for status...
Site "east" is configured. Check the status to see when it is ready

You can use skupper site status at any time to check the status of your site.

Step 6: Link your sites

A Skupper link is a channel for communication between two sites. Links serve as a transport for application connections and requests.

Creating a link requires the use of two Skupper commands in conjunction: skupper token issue and skupper token redeem. The skupper token issue command generates a secret token that can be transferred to a remote site and redeemed for a link to the issuing site. The skupper token redeem command uses the token to create the link.

Note: The link token is truly a secret. Anyone who has the token can link to your site. Make sure that only those you trust have access to it.

First, use skupper token issue in West to generate the token. Then, use skupper token redeem in East to link the sites.

West:

skupper token issue ~/east-to-west.token

East:

skupper token redeem ~/east-to-west.token

If your terminal sessions are on different machines, you may need to use scp or a similar tool to transfer the token securely. By default, tokens expire after a single use or 15 minutes after being issued.

Step 7: Deploy the iperf3 servers

After creating the application router network, deploy iperf3 in each namespace.

East:

kubectl apply -f deployment-iperf3-a.yaml

West:

kubectl apply -f deployment-iperf3-b.yaml

Step 8: Create connectors for the iperf3 servers

With Skupper v2, connectors run in the namespace where the workload is deployed. Create a connector for each iperf3 server so the application network can reach the pods.

East:

skupper connector create iperf3-server-a 5201 --workload deployment/iperf3-server-a

West:

skupper connector create iperf3-server-b 5201 --workload deployment/iperf3-server-b

Step 9: Create listeners for the iperf3 services

Listeners create service endpoints in each namespace so clients can reach those connectors. Configure listeners for every iperf3 service in each namespace.

East:

skupper listener create iperf3-server-a 5201
skupper listener create iperf3-server-b 5201

West:

skupper listener create iperf3-server-a 5201
skupper listener create iperf3-server-b 5201

Step 10: Run benchmark tests across the clusters

After deploying the iperf3 servers into the private and public cloud clusters, the virtual application network enables communications even though they are running in separate clusters.

East:

kubectl exec $(kubectl get pod -l application=iperf3-server-a -o=jsonpath='{.items[0].metadata.name}') -- iperf3 -c iperf3-server-a > results/east-to-a.log
kubectl exec $(kubectl get pod -l application=iperf3-server-a -o=jsonpath='{.items[0].metadata.name}') -- iperf3 -c iperf3-server-b > results/east-to-b.log

West:

kubectl exec $(kubectl get pod -l application=iperf3-server-b -o=jsonpath='{.items[0].metadata.name}') -- iperf3 -c iperf3-server-a > results/west-to-a.log
kubectl exec $(kubectl get pod -l application=iperf3-server-b -o=jsonpath='{.items[0].metadata.name}') -- iperf3 -c iperf3-server-b > results/west-to-b.log
skupper debug dump

Cleaning up

To remove Skupper and the other resources from this exercise, use the following commands.

East:

kubectl delete deployment iperf3-server-a
skupper delete

West:

kubectl delete deployment iperf3-server-b
skupper delete

Next steps

• Find more examples

About this example

This example was produced using Skewer, a library for documenting and testing Skupper examples.

Skewer provides utility functions for generating the README and running the example steps. Use the ./plano command in the project root to see what is available.

To quickly stand up the example using Minikube, try the ./plano demo command.