Hi everyone!
I'm asking for help in understanding how QoS works, and how to debug correctly when QoS problems occur.
About the problem:
I have 2 security gateways with hosts behind them:
Gateway A has hosts 192.168.1.1 and 192.168.2.2.
Behind gateway B - hosts 192.168.3.1 and 192.168.4.2.
I enable the QoS module and configure the Simple rule and apply it. I configure the rule to target traffic between hosts 192.168.1.1 and 192.168.3.1. I create a load between the other hosts.
I made a rule with a guaranteed bandwidth of 200 Mb/sec. I have attached a photo of the rules from both gateways.
Rules were created on external interfaces of both gateways. The total channel speed is 307 Mb/sec.
As a result, when running Iperf3 between hosts (target and load) the speed does not reach 200 mb/sec according to the rule. In waves the speed varies from 30 to 170 Mb/sec. And on the channel with load the speed is 5-7 mb/sec. As a result, the total utilisation reaches 80%! The QoS module itself works, because under the condition of LIMIT, the speed is really limited. Also the guaranteed bandwidth works if you don't run Iperf on other hosts to create load.
I am asking for help or ideas on how to solve the problem and how to debug correctly.
Thank you in advance for your help!