QoS - Is "Real-Time" Priority a Strict Priority Queue?

[michaelmertens]

So I have two questions regarding PAN QoS when you use class 1 (or any class) and configure it with a priority of "real-time".
1) I assume Real-Time makes it a priority queue. Is it a STRICT priority queue? (Meaning that whatever you set that rate for, if there's more of that type traffic than what the rate is, even if THERE IS available bandwidth, the excess rate will be dropped?

2) Does QoS queuing ONLY get engage when the interface is congested? 

Thanks!

Mike

[SCantwell_IM · Accepted solution]

Good Day

For the first question, based on my experience, the answer is YES.

For the 2nd question, the answer is NO.

[michaelmertens]

Steve, thank you- that confirms what I experienced and what my mistake was.

THANKS!

[psycoma1984]

Hi,

What the difference between 'real-time' and 'high' priority than? Will there be any difference under similar circumstances when you have 100 Mbit/s MAX egress and 50 Mbit/s guarantee, while actual traffic matching this class exceeding 100 Mbit/s? Previously I was under impression that real-time one will just drop traffic exceeding queue limit and anything else will just reclassify everything above to default class 4. 

Is this correct assumption?