QoS-Adherence-Supervision

Tested on Ubuntu 20.04.6 LTS (Focal Fossa)
The agent polls a switch (Red Lion) over Telnet (default port 23) for Tx counters every second from the Secondary.
These values were called QoS statistics, according to the switch documentation.
If the Tx counters are below or above an expected threshold (1050), the agent sends appropriate Access Control List (ACL) to correct the Quality of Service (QoS) switch configuration by re-prioritizing traffic flows.
Can be adapted for any traffic flows, currently only implemented for three different flows (High priority UDP-based heartbeats, Medium priority Telnet, and Low priority UDP traffic).

Topology:
Primary ------ Red Lion switch ------ Cisco switch ------ Secondary

Installation

Install the required packages and libraries.

sudo apt update 
sudo apt upgrade
sudo apt-get install build-essential
sudo apt install cmake
sudo apt install net-tools
sudo apt-get install libboost-all-dev

Usage

Upload and apply switch configuration:

1. Red Lion, Model: NT-4008-000-PN-M, Firmware: 1.0.9
2. Cisco, Model: IE-2000-8TC-L, IOS: 15.2(7)E2

Change the priority of the network interrupts for each core, by first finding the PID of each process

ps -A | grep ksoftirq

And then elevating the priority to 98

sudo chrt -p 98 PID

Build and run the code:

1. Build and run the QoS agent on the secondary controller with maximum priority.

sudo g++ -o qos qos.cpp -pthread 
sudo chrt --fifo 99 ./qos

Long and short CLI for the Red Lion switch

Querying the QoS statistics on interface 1/2, filtering out unnecessary data

show interface GigabitEth 1/2 statistics | include Tx Priority 7:
sh int G 1/2 stati | i Tx Priority 7:

Re-marking matching L3 DSCP 56 packets on interface 1/1 to L2 CoS 7

qos qce 1 interface GigabitEth 1/1 frame-type ipv4 dscp 56 action cos 7
q q 1 int G 1/1 f ipv4 ds 56 a c 7

Marking all other [UDP or TCP] packets with L2 CoS 0, on interfaces 1/1, 1/2, and 1/8

qos qce 2 interface GigabitEth 1/1-2,8 frame-type ipv4 proto [UDP/TCP] action cos 0
q q 2 int G 1/1-2,8 f ipv4 p [U/T] a c 0

Marking TCP traffic toward destination port 23 with L2 CoS 6

qos qce 3 frame-type ipv4 proto TCP dport 23 action cos 6
q q 3 int f ipv4 p t d 23 a c 6