openstack/kuryr-kubernetes
Code Issues Proposed changes

[DOCS] Testing SCTP service support

Browse Source 
Includes instructions for creating K8s services with SCTP
protocol and verifying Kuryr-kubernetes SCTP support.
To-do: Kuryr tempest tests.

Partially-Implements: blueprint sctp-support
Change-Id: I89590e5b04bb87936954bb46a4bb1a9a14540a00
This commit is contained in:
Tabitha 2021-01-11 12:26:32 +01:00
parent e69989c6e4
commit 329fc5f5f8
3 changed files with 241 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
contrib/sctp_client.py Normal file
View File

@ -0,0 +1,31 @@
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import sctp
import socket
import sys
sk = sctp.sctpsocket_tcp(socket.AF_INET)
def connect_plus_message(OUT_IP, OUT_PORT):
sk.connect((OUT_IP, OUT_PORT))
print("Sending Message")
sk.sctp_send(msg='HELLO, I AM ALIVE!!!')
msgFromServer = sk.recvfrom(1024)
print(msgFromServer[0].decode('utf-8'))
sk.shutdown(0)
sk.close()
if __name__ == '__main__':
connect_plus_message(sys.argv[1], int(sys.argv[2]))

1
doc/source/installation/index.rst
View File

@ -46,3 +46,4 @@ This section describes how you can install and configure kuryr-kubernetes
sriov
testing_udp_services
testing_sriov_functional
testing_sctp_services

209
doc/source/installation/testing_sctp_services.rst Normal file
View File

@ -0,0 +1,209 @@
=====================
Testing SCTP Services
=====================
In this example, we will use the `kuryr-sctp-demo`_ image. This image
implements a SCTP server that listens on port 9090, and responds to client
when a packet is received.
We first create a deployment named sctp-demo using the deployment manifest
(deploy.yml) below:
.. code-block:: yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: sctp-demo
labels:
app: server
spec:
replicas: 2
selector:
matchLabels:
app: server
template:
metadata:
labels:
app: server
spec:
containers:
- name: sctp-demo
image: tabbie/kuryr-sctp-demo:v2.1
ports:
- containerPort: 9090
.. code-block:: console
$ kubectl apply -f deploy.yml
deployment.apps/sctp-demo created
At this point we should have two pods running the `kuryr-sctp-demo`_ image:
.. code-block:: console
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
sctp-demo-65fcf85ddb-8vnrq 1/1 Running 0 40s
sctp-demo-65fcf85ddb-zg7nq 1/1 Running 0 109s
Next, we expose the deployment as a service, setting SCTP port to 90:
.. note::
In order to successfully expose the deployment as a service, ensure that
the Octavia provider in use by Kuryr has SCTP support.
.. code-block:: console
$ kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.0.0.129 <none> 443/TCP 36h
$ kubectl expose deploy/sctp-demo --protocol=SCTP --port=90 --target-port=9090
service/sctp-demo exposed
$ kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.0.0.129 <none> 443/TCP 36h
sctp-demo ClusterIP 10.0.0.158 <none> 90/SCTP 42s
Now, let's check the OpenStack load balancer created by Kuryr for **sctp-demo**
service.
.. code-block:: console
$ openstack loadbalancer list
+--------------------------------------+--------------------+----------------------------------+-------------+---------------------+----------+
| id | name | project_id | vip_address | provisioning_status | provider |
+--------------------------------------+--------------------+----------------------------------+-------------+---------------------+----------+
| 4d219ac7-2592-4d33-8afa-12994c5d82ec | default/kubernetes | 2e89a9e0a50d42d1be8054a80530b836 | 10.0.0.129 | ACTIVE | amphora |
| 96b38be3-1183-41c5-a0db-d246ef1d07cb | default/sctp-demo | 2e89a9e0a50d42d1be8054a80530b836 | 10.0.0.158 | ACTIVE | amphora |
+--------------------------------------+--------------------+----------------------------------+-------------+---------------------+----------+
$ openstack loadbalancer show default/sctp-demo
+---------------------+--------------------------------------+
| Field | Value |
+---------------------+--------------------------------------+
| admin_state_up | True |
| availability_zone | None |
| created_at | 2021-01-11T10:01:15 |
| description | |
| flavor_id | None |
| id | 96b38be3-1183-41c5-a0db-d246ef1d07cb |
| listeners | eda5caa0-083a-4c45-a2e5-38c243b2c970 |
| name | default/sctp-demo |
| operating_status | ONLINE |
| pools | 0935f099-d901-4f39-8090-392a527cbc35 |
| project_id | 2e89a9e0a50d42d1be8054a80530b836 |
| provider | amphora |
| provisioning_status | ACTIVE |
| updated_at | 2021-01-11T10:05:30 |
| vip_address | 10.0.0.158 |
| vip_network_id | 13190422-869c-4259-ba3b-6a41be79a671 |
| vip_port_id | 64da8e72-8469-4ac6-a0e6-ec60ca02b96a |
| vip_qos_policy_id | None |
| vip_subnet_id | 0041469e-371c-417f-83df-94ca8f202eab |
+---------------------+--------------------------------------+
Checking the load balancer's details, we can see that the load balancer is
listening on SCTP port 90:
.. code-block:: console
$ openstack loadbalancer listener show eda5caa0-083a-4c45-a2e5-38c243b2c970
+-----------------------------+--------------------------------------+
| Field | Value |
+-----------------------------+--------------------------------------+
| admin_state_up | True |
| connection_limit | -1 |
| created_at | 2021-01-11T10:04:31 |
| default_pool_id | 0935f099-d901-4f39-8090-392a527cbc35 |
| default_tls_container_ref | None |
| description | |
| id | eda5caa0-083a-4c45-a2e5-38c243b2c970 |
| insert_headers | None |
| l7policies | |
| loadbalancers | 96b38be3-1183-41c5-a0db-d246ef1d07cb |
| name | default/sctp-demo:SCTP:90 |
| operating_status | ONLINE |
| project_id | 2e89a9e0a50d42d1be8054a80530b836 |
| protocol | SCTP |
| protocol_port | 90 |
| provisioning_status | ACTIVE |
| sni_container_refs | [] |
| timeout_client_data | 50000 |
| timeout_member_connect | 5000 |
| timeout_member_data | 50000 |
| timeout_tcp_inspect | 0 |
| updated_at | 2021-01-11T10:05:30 |
| client_ca_tls_container_ref | None |
| client_authentication | NONE |
| client_crl_container_ref | None |
| allowed_cidrs | None |
| tls_ciphers | None |
| tls_versions | None |
| alpn_protocols | None |
+-----------------------------+--------------------------------------+
And the load balancer has a pool with two members listening on SCTP port 9090:
.. code-block:: console
$ openstack loadbalancer pool list
+--------------------------------------+---------------------------+----------------------------------+---------------------+----------+--------------+----------------+
| id | name | project_id | provisioning_status | protocol | lb_algorithm | admin_state_up |
+--------------------------------------+---------------------------+----------------------------------+---------------------+----------+--------------+----------------+
| c69a87a5-078e-4c2b-84d4-0a2691c58f07 | default/kubernetes:443 | 2e89a9e0a50d42d1be8054a80530b836 | ACTIVE | HTTPS | ROUND_ROBIN | True |
| 0935f099-d901-4f39-8090-392a527cbc35 | default/sctp-demo:SCTP:90 | 2e89a9e0a50d42d1be8054a80530b836 | ACTIVE | SCTP | ROUND_ROBIN | True |
+--------------------------------------+---------------------------+----------------------------------+---------------------+----------+--------------+----------------+
$ openstack loadbalancer member list default/sctp-demo:SCTP:90
+--------------------------------------+-----------------------------------------+----------------------------------+---------------------+-----------+---------------+------------------+--------+
| id | name | project_id | provisioning_status | address | protocol_port | operating_status | weight |
+--------------------------------------+-----------------------------------------+----------------------------------+---------------------+-----------+---------------+------------------+--------+
| abeec334-56b1-4535-a238-71424d78590e | default/sctp-demo-65fcf85ddb-zg7nq:9090 | 2e89a9e0a50d42d1be8054a80530b836 | ACTIVE | 10.0.0.75 | 9090 | NO_MONITOR | 1 |
| 826345b0-1264-421d-b9e0-8756f7bc0d21 | default/sctp-demo-65fcf85ddb-8vnrq:9090 | 2e89a9e0a50d42d1be8054a80530b836 | ACTIVE | 10.0.0.88 | 9090 | NO_MONITOR | 1 |
+--------------------------------------+-----------------------------------------+----------------------------------+---------------------+-----------+---------------+------------------+--------+
At this point, we have both the kubernetes service and corresponding OpenStack
load balancer running, and we are ready to run the client application.
For the client application we will use the `sctp_client`_ python script. The
SCTP client script sends SCTP message towards specific IP and port, and waits
for a response from the server. The client application communicates with the
server by leveraging OpenStack load balancer functionality.
For the client application to work, python SCTP module needs to be installed
in our environment. We need a SCTP-aware kernel (most are). First we install
the following packages: libsctp-dev, libsctp1, lksctp-tools and then install
the module.
.. code-block:: console
$ sudo apt-get install libsctp-dev libsctp1 lksctp-tools
$ pip3 install pysctp
And we need the SCTP server service IP and port:
.. code-block:: console
$ kubectl get svc sctp-demo
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
sctp-demo ClusterIP 10.0.0.158 <none> 90/SCTP 67m
Last step will be to connect to the SCTP server service:
.. code-block:: console
$ python3 sctp_client.py 10.0.0.158 90
Sending Message
sctp-demo-65fcf85ddb-zg7nq: HELLO, I AM ALIVE!!!
$ python3 sctp_client.py 10.0.0.158 90
Sending Message
sctp-demo-65fcf85ddb-8vnrq: HELLO, I AM ALIVE!!!
.. _kuryr-sctp-demo: https://hub.docker.com/repository/docker/tabbie/kuryr-sctp-demo
.. _sctp_client: https://github.com/openstack/kuryr-kubernetes/blob/master/contrib/sctp_client.py