kuryr-kubernetes/doc/source/installation/testing_connectivity.rst

Testing Network Connectivity

Once the environment is ready, we can test that network connectivity works among pods. First we check the status of the kubernetes cluster:

$ kubectl get nodes
NAME           STATUS    AGE       VERSION
masterodl-vm   Ready     1h        v1.6.2

$ kubectl get pods
No resources found.

$ kubectl get svc
NAME         CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
kubernetes   10.0.0.129   <none>        443/TCP   1h

As we can see, this is a one node cluster with currently no pods running, and with the kubernetes API service listening on port 443 at 10.0.0.129 (which matches the ip assigned to the load balancer created for it).

To test proper configuration and connectivity we firstly create a sample deployment with:

$ kubectl run demo --image=celebdor/kuryr-demo
deployment "demo" created

After a few seconds, the container is up an running, and a neutron port was created with the same IP that got assigned to the pod:

$ kubectl get pods
NAME                    READY     STATUS    RESTARTS   AGE
demo-2293951457-j29nb   1/1       Running   0          1m

$ kubectl describe pod demo-2293951457-j29nb | grep IP:
IP:             10.0.0.69

$ openstack port list | grep demo
| 73100cdb-84d6-4f33-93b2-e212966c65ac | demo-2293951457-j29nb | fa:16:3e:99:ac:ce | ip_address='10.0.0.69', subnet_id='3c3e18f9-d1d0-4674-b3be-9fc8561980d3' | ACTIVE |

We can then scale the deployment to 2 pods, and check connectivity between them:

$ kubectl scale deploy/demo --replicas=2
deployment "demo" scaled

$ kubectl get pods
NAME                    READY     STATUS    RESTARTS   AGE
demo-2293951457-gdrv2   1/1       Running   0          9s
demo-2293951457-j29nb   1/1       Running   0          14m

$ openstack port list | grep demo
| 73100cdb-84d6-4f33-93b2-e212966c65ac | demo-2293951457-j29nb | fa:16:3e:99:ac:ce | ip_address='10.0.0.69', subnet_id='3c3e18f9-d1d0-4674-b3be-9fc8561980d3' | ACTIVE |
| 95e89edd-f513-4ec8-80d0-36839725e62d | demo-2293951457-gdrv2 | fa:16:3e:e6:b4:b9 | ip_address='10.0.0.75', subnet_id='3c3e18f9-d1d0-4674-b3be-9fc8561980d3' | ACTIVE |

$ kubectl exec -it demo-2293951457-j29nb -- /bin/sh

sh-4.2$ curl 10.0.0.69:8080
demo-2293951457-j29nb: HELLO, I AM ALIVE!!!

sh-4.2$ curl 10.0.0.75:8080
demo-2293951457-gdrv2: HELLO, I AM ALIVE!!!

sh-4.2$ ping 10.0.0.75
PING 10.0.0.75 (10.0.0.75) 56(84) bytes of data.
64 bytes from 10.0.0.75: icmp_seq=1 ttl=64 time=1.14 ms
64 bytes from 10.0.0.75: icmp_seq=2 ttl=64 time=0.250 ms

Next, we expose the service so that a neutron load balancer is created and the service is exposed and load balanced among the available pods:

$ kubectl get svc
NAME         CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
kubernetes   10.0.0.129   <none>        443/TCP   1h

$ kubectl expose deploy/demo --port=80 --target-port=8080
service "demo" exposed

$ kubectl get svc
NAME         CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
demo         10.0.0.161   <none>        80/TCP    6s
kubernetes   10.0.0.129   <none>        443/TCP   1h

$ neutron lbaas-loadbalancer-list
+--------------------------------------+--------------------+----------------------------------+-------------+---------------------+----------+
| id                                   | name               | tenant_id                        | vip_address | provisioning_status | provider |
+--------------------------------------+--------------------+----------------------------------+-------------+---------------------+----------+
| 7d0cf5b5-b164-4b32-87d3-ae6c82513927 | default/kubernetes | 47c28e562795468ea52e92226e3bc7b1 | 10.0.0.129  | ACTIVE              | haproxy  |
| c34c8d0c-a683-497f-9530-a49021e4b502 | default/demo       | 49e2683370f245e38ac2d6a8c16697b3 | 10.0.0.161  | ACTIVE              | haproxy  |
+--------------------------------------+--------------------+----------------------------------+-------------+---------------------+----------+

$ neutron lbaas-listener-list
+--------------------------------------+--------------------------------------+------------------------+----------------------------------+----------+---------------+----------------+
| id                                   | default_pool_id                      | name                   | tenant_id                        | protocol | protocol_port | admin_state_up |
+--------------------------------------+--------------------------------------+------------------------+----------------------------------+----------+---------------+----------------+
| fc485508-c37a-48bd-9be3-898bbb7700fa | b12f00b9-44c0-430e-b1a1-e92b57247ad2 | default/demo:TCP:80    | 49e2683370f245e38ac2d6a8c16697b3 | TCP      |            80 | True           |
| abfbafd8-7609-4b7d-9def-4edddf2b887b | 70bed821-9a9f-4e1d-8c7e-7df89a923982 | default/kubernetes:443 | 47c28e562795468ea52e92226e3bc7b1 | HTTPS    |           443 | True           |
+--------------------------------------+--------------------------------------+------------------------+----------------------------------+----------+---------------+----------------+

$ neutron lbaas-pool-list
+--------------------------------------+------------------------+----------------------------------+--------------+----------+----------------+
| id                                   | name                   | tenant_id                        | lb_algorithm | protocol | admin_state_up |
+--------------------------------------+------------------------+----------------------------------+--------------+----------+----------------+
| 70bed821-9a9f-4e1d-8c7e-7df89a923982 | default/kubernetes:443 | 47c28e562795468ea52e92226e3bc7b1 | ROUND_ROBIN  | HTTPS    | True           |
| b12f00b9-44c0-430e-b1a1-e92b57247ad2 | default/demo:TCP:80    | 49e2683370f245e38ac2d6a8c16697b3 | ROUND_ROBIN  | TCP      | True           |
+--------------------------------------+------------------------+----------------------------------+--------------+----------+----------------+

$ neutron lbaas-member-list default/demo:TCP:80
+--------------------------------------+------------------------------------+----------------------------------+-----------+---------------+--------+--------------------------------------+----------------+
| id                                   | name                               | tenant_id                        | address   | protocol_port | weight | subnet_id                            | admin_state_up |
+--------------------------------------+------------------------------------+----------------------------------+-----------+---------------+--------+--------------------------------------+----------------+
| c0057ce6-64da-4613-b284-faf5477533ab | default/demo-2293951457-j29nb:8080 | 49e2683370f245e38ac2d6a8c16697b3 | 10.0.0.69 |          8080 |      1 | 55405e9d-4e25-4a55-bac2-e25ee88584e1 | True           |
| 7a0c0ef9-35ce-4134-b92a-2e73f0f8fe98 | default/demo-2293951457-gdrv2:8080 | 49e2683370f245e38ac2d6a8c16697b3 | 10.0.0.75 |          8080 |      1 | 55405e9d-4e25-4a55-bac2-e25ee88584e1 | True           |
+--------------------------------------+------------------------------------+----------------------------------+-----------+---------------+--------+--------------------------------------+----------------+

We can see that both pods are included as members and that the demo cluster-ip matches with the loadbalancer vip_address. In order to check loadbalancing among them, we are going to curl the cluster-ip from one of the pods and see that each of the pods is replying at a time:

$ kubectl exec -it demo-2293951457-j29nb -- /bin/sh

sh-4.2$ curl 10.0.0.161
demo-2293951457-j29nb: HELLO, I AM ALIVE!!!

sh-4.2$ curl 10.0.0.161
demo-2293951457-gdrv2: HELLO, I AM ALIVE!!!