LACP not working - Mikrotik Switch

[Banobano]

SOLVED

The issue was on the Mikrotik side - or my understanding of their implementation (which is not fully documented).

SwOS needs at least two physical links to form a dynamic link aggregation via LACP. Testing with one interface does not work.

Initial issue
Hi together,

I'm trying to set up an untagged LACP link aggregation with 2 LAN interfaces, connected to my Mikrotik Switch running the SwOS operating system (CRS326). Sadly it doesn't work after spending many hours. Right now, I'm testing with one interface (em0) to have a MGMT fallback (re0).

My switch is capable to talk LACP passive and active. I set the link to active and the MAC of the pfSense shows up. My switch and the pfSense tell me the link is up and running I guess (pfSense shows me "Link up" in the dashboard), but the pfSense cannot ping clients in the same subnet as the LAGG.

Configured Interfaces:

• WAN: Disconnected on purpose
• LAN: Not working, this is the issue - IP 192.168.1.1 /24, assigned to LAGG0 interface (Only physical interface em0 assigned)
• OPT1: Working as intended - IP 192.168.0.254 /24, assigned to re0 interface (Mgmt until LAGG is working)

When I set the interface LAN back to my physical interface em0, the IP is pingable from all clients. It seems to be an issue with the LAGG.

I'd appreciate your help, please look up following screenshots:

Switch Config
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pfSense Config
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Thanks a lot and stay healthy!

[stephenw10]

LACP lagg on em is a common deployment. It well tried and tested. Not so much a single port lagg but that should also work fine. The config you have there in pfSense looks fine.
I would be looking at the switch end. The one screenshot of that I see looks odd. What is that we are looking at where re0 is set as 'passive'?

Steve

[Banobano]

SOLVED

The issue was on the Mikrotik side - or my understanding of their implementation.

SwOS needs at least two physical links to form a dynamic link aggregation via LACP. Testing with one interface does not work.

[Derelict]

That's broken, but it's Mikrotik. What happens if you get the LACP up but go down to one link?