Two bridges with the same MAC address

RouterOS General
1

I have the CRS504 (4 port 100Gbps) switch in a very simple configuration almost straight out of the box with 2 bridges:

“Mgmt”: contains just the mgmt port.
”bridge”: contains all the qsfp ports.

I noticed that I have activity on 3 of my plugged-in qsfp ports but zero traffic showing on “bridge”. I then noticed that the MAC address of both bridges is the same. I did not configure it like this and i am hesitant to make any changes as it is now in production. So a few questions:

  1. Is this normal/expected?
  2. Why is there zero traffic on “bridge” even though three of its ports have activity?
  3. Why does Torch showing nothing on the 3 ports, even though there is activity? For example, I run a ping from one device to another and I would expect to see the icmp traffic when Torching the ports.

Thanks

2

Having same MAC on different bridges is awkward but doesn’t necessarily break anything … as long as they don’t become part of same L2 network.

Bridge has different personalities (read more in this article). MAC address is only used by “the switch-facing interface of the router”, “bridge activity” is also about same entity.

Torch will only see trafic between two switched ports if it’s not HW offloaded. Your switch is a very good one and can offload (almost) everything to switch chip (it’s the only way to consistently reach wire-speed transfers), so it’s normal you don’t see traffic. If you have to sniff traffic, first disable HW offload on port you want to check.

3

Thank you for the reply.