Test the Network Connectivity

iPerf is a tool commonly used to measure network performance, perform network tuning, and more. The iPerf application consists of two main services, iperf-sleep (client) and iperf-server.

Prerequisites for using the iPerf Tool

To deploy a application, you must create a namespace for that application in both the client and server clusters before creating the slice.

Create the iperf namespace on the worker clusters identified as the client and server using the following command:

kubectl create ns iperf

Deploy the iPerf Application

Deploy the iPerf application and test the network connectivity between the worker clusters.

info

You can also use an intra-cluster slice to test the intra cluster connectivity. To know more, see deploying the iPerf application on an intra-cluster slice.

Identify a worker cluster as a client and another worker cluster as a server and configure them to test the network connectivity.

To establish the connectivity between two worker clusters:

1. Switch context to the worker cluster identified as the client using the following command:

   kubectx <cluster name>

2. Onboard the existing iperf namespace to the slice. To know more, see onboarding namespaces.

   caution

   Ensure that you have onboarded the iperf namespace. If you create a namespace after the slice creation, then you could face issues when you deploy the application as the namespace creation takes some time.

3. Create the iperf-sleep.yaml using the following template.

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: iperf-sleep
     namespace: iperf
     labels:
       app: iperf-sleep
   spec:
     replicas: 1
     selector:
       matchLabels:
         app: iperf-sleep
     template:
       metadata:
         labels:
           app: iperf-sleep
       spec:
         containers:
         - name: iperf
           image: mlabbe/iperf
           imagePullPolicy: Always
           command: ["/bin/sleep", "3650d"]
         - name: sidecar
           image: nicolaka/netshoot
           imagePullPolicy: IfNotPresent
           command: ["/bin/sleep", "3650d"]
           securityContext:
             capabilities:
               add: ["NET_ADMIN"]
             allowPrivilegeEscalation: true
             privileged: true

4. Apply theiperf-sleep.yaml using the following command:

   kubectl apply -f iperf-sleep.yaml -n iperf

5. Validate the iPerf client by checking if the pods are running on the worker cluster using the following command:

   kubectl get pods -n iperf

   Expected Output

   NAME                           READY   STATUS    RESTARTS   AGE
   iperf-sleep-676b945fbf-9l9h7   3/3     Running   0          60s

6. Switch context to the worker cluster identified as the server using the following command:

   kubectx <cluster name>

7. Onboard the existing iperf namespace on the slice. To know more, see onboarding namespaces.

   caution

   Ensure that you have onboarded the iperf namespace. If you create a namespace after the slice creation, then you could face issues when you deploy the application as the namespace creation takes some time.

8. Create the iperf-server.yaml file using the following template.

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: iperf-server
     namespace: iperf
     labels:
       app: iperf-server
   spec:
     replicas: 1
     selector:
       matchLabels:
         app: iperf-server
     template:
       metadata:
         labels:
           app: iperf-server
       spec:
         containers:
         - name: iperf
           image: mlabbe/iperf
           imagePullPolicy: Always
           args:
             - '-s'
             - '-p'
             - '5201'
           ports:
           - containerPort: 5201
             name: server
         - name: sidecar
           image: nicolaka/netshoot
           imagePullPolicy: IfNotPresent
           command: ["/bin/sleep", "3650d"]
           securityContext:
             capabilities:
               add: ["NET_ADMIN"]
             allowPrivilegeEscalation: true
             privileged: true
   ---
   apiVersion: networking.kubeslice.io/v1beta1
   kind: ServiceExport
   metadata:
     name: iperf-server
     namespace: iperf
   spec:
     slice: <slicename> # water
     selector:
       matchLabels:
         app: iperf-server
     ingressEnabled: false
     ports:
     - name: tcp
       containerPort: 5201
       protocol: TCP

9. Apply the iperf-server.yaml configured in the worker cluster using the following command:

   kubectl apply -f iperf-server.yaml -n iperf

10. Validate the iPerf server by checking if the pods are running on the worker cluster using the following command:

    kubectl get pods -n iperf

    Expected Output

    NAME                            READY   STATUS    RESTARTS   AGE
    iperf-server-7889799774-s5zrs   3/3     Running   0          60s

11. Validate the service export of the iPerf server on the worker clusters using the following command:

    kubectl get serviceexport -n iperf

    Expected Output

    NAME           SLICE   INGRESS   PORT(S)    ENDPOINTS   STATUS
    iperf-server   water             5201/TCP   1           READY

12. Validate the service import of the iPerf server on the worker cluster using the following command:

    kubectl get serviceimport -n iperf

    Expected Output

    NAME           SLICE   PORT(S)    ENDPOINTS   STATUS
    iperf-server   water   5201/TCP   1           READY

13. Validate the service import of the iPerf client on the other worker cluster by running the following command:

    kubectl get serviceimport -n iperf

    Expected Output

    NAME           SLICE   PORT(S)    ENDPOINTS   STATUS
    iperf-server   water   5201/TCP   1           READY

14. Switch context to the iperf client cluster using the following command:

    kubectx <cluster name>

15. Check the connectivity from the iPerf client by using the following command:

    kubectl exec -it deploy/iperf-sleep -c iperf -n iperf -- iperf -c iperf-server.iperf.svc.slice.local -p 5201 -i 1 -b 10Mb;

    Expected Output

    ------------------------------------------------------------
    Client connecting to iperf-server.iperf.svc.slice.local, TCP port 5201
    TCP window size: 45.0 KByte (default)
    ------------------------------------------------------------
    [  1] local 10.1.1.5 port 58116 connected with 10.1.2.5 port 5201
    [ ID] Interval       Transfer     Bandwidth
    [  1] 0.00-1.00 sec   640 KBytes  5.24 Mbits/sec
    [  1] 1.00-2.00 sec   640 KBytes  5.24 Mbits/sec
    [  1] 2.00-3.00 sec   640 KBytes  5.24 Mbits/sec
    [  1] 3.00-4.00 sec   512 KBytes  4.19 Mbits/sec
    [  1] 4.00-5.00 sec   640 KBytes  5.24 Mbits/sec
    [  1] 5.00-6.00 sec   768 KBytes  6.29 Mbits/sec
    [  1] 6.00-7.00 sec   512 KBytes  4.19 Mbits/sec
    [  1] 7.00-8.00 sec   512 KBytes  4.19 Mbits/sec
    [  1] 8.00-9.00 sec   512 KBytes  4.19 Mbits/sec
    [  1] 9.00-10.00 sec   768 KBytes  6.29 Mbits/sec
    [  1] 10.00-10.45 sec   384 KBytes  7.04 Mbits/sec
    [  1] 0.00-10.45 sec  6.38 MBytes  5.12 Mbits/sec

    success

    The connectivity between the worker clusters on a slice is successful!