SDN Load Balancer on OpenStack SDN/NFV platform

Prerequisites

• python3.7
• pip3

Installation

Clone the repository

git clone https://github.com/themisAnagno/SDN_Load_Balancer.git
cd SDN_Load_Balancer

Create the Virtual Environment.

pip3 install virtualenv
virtualenv venv --python=python3.7
source venv/bin/activate

Install the requirements

pip3 install -r requirements.txt

Start the Load Balancer Application

venv/bin/gunicorn -b 0.0.0.0:8001 --access-logfile - --chdir $(pwd) "lb_api:create_app()"

Introduction

SDN Load Balancer is instantiated as a VNF on the SDN/NFV platform. Users of the platform are connected to both VLC/mmWave and Wi-Fi Access Networks at the same time, and we assume that they can receive and transmit traffic to any of the two networks, using as default-gateways the Virtual L3 Router inside OpenStack, as shown in Figure below. The default option is to route traffic through the VLC/mmWave Access Network. The Load Balancer uses the Ryu SDN controller in order to monitor the incoming/outgoing traffic at the interface connected to the VLC/mmWave Access Network. Depending on the traffic and the defined upper and lower bitrate limits, the Load Balancer can take one of the following decisions: • Route the traffic of a user to the Wi-Fi Access Network, if the monitored traffic is above the upper bitrate limit. • Route the traffic of a user that was connected to the Wi-Fi back to the VLC/mmWave Access Network, if the monitored traffic is below the lower bitrate limit.

Initial Parameters

Load Balancer requires some initial operational parameters to be set. These parameters are described in a json file that is called initial_config.json. The template of this file is presented below:

{
    "upper_bw_limit": <integer>,
    "lower_bw_limit": <integer>,
    "ryu_ip": <string>,
    "br-int_dpid": <string>,
    "vlc_of_port": <integer>,
    "external_of_port": <integer>,
    "wifi_vlan": <integer>,
    "interval": <integer> 
}

Field	Description
upper_bw_limit	The upper bitrate limit [Mbps]
lower_bw_limi	The lower bitrate limit [Mbps]
ryu_ip	The IP of the Ryu controller
br-int_dpid	The dpid of the br-int OVS bridge on OpenStack
vlc_of_port	The OpenFlow port value of the VLC interface on the br-int bridge
external_of_port	The OpenFlow port value of the external interface on the br-int bridge
wifi_vlan	The VLAN used by OpenStack for the Wifi provider network
interval	The time between each Load Balancer traffic measurement [seconds]

There are two ways to define the initial operational parameters:

1. Use the cloud-init service, adding a cloud-config file, either via the OpenStack, or via the NFV Orchestrator (i.e. Open Source MANO). An example of a cloud-config.yaml file is presented below:

#cloud-config
# vim: syntax=yaml
#
write_files:
  - path: /home/iorl/SDN_Load_Balancer/init_config.json
    content: |
      {
        "upper_bw_limit": 40,
        "lower_bw_limit": 20,
        "ryu_ip": "10.100.128.2",
        "br-int_dpid": "182816038959173",
        "vlc_of_port": 12,
          "external_of_port": 2,
        "wifi_vlan": 2,
        "interval": 20
      }
    permissions: "0644"

2. Use the North Bound Interface REST API.

Users

The SDN Load Balancer administrator has to define the list of users that are connected on the IoRL Access Networks. This list matches for each user his/her IP on the Wi-Fi network with his/her IP on the VLC/mmWave network. This is list is a json file given to the Load Balancer via the REST API. The file below presents an example of such list:

{
    "users": [
        {
            "vlc_ip": "10.100.131.18",
            "wifi_ip": "10.100.130.56"
        },
        {
            "vlc_ip": "10.100.131.30",
            "wifi_ip": "10.100.130.57"
        },
        {
            "vlc_ip": "10.100.131.31",
            "wifi_ip": "10.100.130.58"
        },
        {
            "vlc_ip": "10.100.131.32",
            "wifi_ip": "10.100.130.59"
        },
        {
            "vlc_ip": "10.100.131.33",
            "wifi_ip": "10.100.130.60"
        },
	{
            "vlc_ip": "10.100.131.34",
            "wifi_ip": "10.100.130.61"
        }
    ]
}

Logs

You can use the SDN Load Balancer NBI REST APIs to retrieve logs of: • Load Balancer Logs • Service Logs Both APIs are described in detail in NBI REST API Section

NBI REST API

For the documentation of the REST APIs, a swagger-ui tool has been integrated to the SDN Load Balancer. Open the http://<load_balancer_IP>:8001/api/docs on a web browser in order to see the swagger page. A screenshot of the swagger-ui is depected in Figure below:

Logs

Method	URI	Data	Description
GET	/api/logs	-	Returns the logs of the Load Balancer Application

Method	URI	Data	Description
GET	/api/service_logs	-	Returns the logs of the Service that implements the Load Balancer Application

Initial Operational Parameters

Method	URI	Data	Description
GET	/api/parameters	-	Returns the operational parameters
PUT	/api/parameters	init_config.json	Sets the operational parameters

Users

Method	URI	Data	Description
GET	/api/users	-	Returns the users list
PUT	/api/users	users.json	Sets the users list
POST	/api/users	users.json	Adds the given users to the existing users list
DELETE	/api/users	users.json	Deletes the given users from the existing users list. If no data are given, the whole users list is deleted

VLC/mmWave users

Method	URI	Data	Description
GET	/api/vlcusers	-	Returns the list of users currently on the VLC/mmWave Access network

Wi-Fi users

Method	URI	Data	Description
GET	/api/wifiusers	-	Returns the list of users currently on the Wi-Fi Access network

Use the SDN Load Balancer VNF

You can download the Load Balancer VNF here. Instantiate the VNF on the SDN/NFV platform using the following minimum resources: • VCPUs: 2 • RAM: 2 GB • Root Disk: 20 GB The Load Balancer service should start immediately with the instantiation of the VNF. To verify that the Load Balancer service has started, try the following REST API call:

curl http://<load_balancer_IP>:8001/api/logs

This should return the logs of the Load Balancer service.

Run the SDN Load Balancer as a service

Run the make_service script. Note that it will need root privileges

./make_service