Hi

One of our customers has two links, one through us, and one through another provider. We simply pass over some tagged vlans for them, via a CCR and at the data-centre another CCR.
They are attempting to create LAG groups on their device to leverage the two diverse trunks provided to them. The Primary links provided over the other network are operational and LACP PDU’s are passing.

For some reason they cannot get LACP to pass through our last mile. Our config is the normal Mikrotik router setup, i.e a bridge with a vlan on the uplink port and a vlan on the access port. There are no bridge filters enabled.

Anything I need to look for?

The destination MAC address of LACP PDUs is 01:80:c2:00:00:02, which is a "link-local" multicast address, so switches that are not totally dumb do not forward such frames. LACP has been designed for interconnection of two adjacent boxes using multiple physical links, not for transiting each slave link via a different L2 path on other switches.

I think a similar situation has been discussed here some months ago, and that the CRS switch chip could be instructed to forward the LACP PDUs. Is your CCR model the one equipped with the 8327 switch chip?

The destination MAC address of LACP PDUs is 01:80:c2:00:00:02, which is a "link-local" multicast address, so switches that are not totally dumb do not forward such frames. LACP has been designed for interconnection of two adjacent boxes using multiple physical links, not for transiting each slave link via a different L2 path on other switches.

I think a similar situation has been discussed here some months ago, and that the CRS switch chip could be instructed to forward the LACP PDUs. Is your CCR model the one equipped with the 8327 switch chip?

Thanks, nope one is a 1036 and the other side at the datacenter is a 1016. Both do not seem to have the atheros 8327 chip, only the ccr 1009 series it seems. So my only options would be to replace equipment just to support their requirement?

In v6.43 and later the standards-compliant behaviour (i.e. that packets destined to 01:80:C2:XX:XX:XX should NOT be forwarded) can be disabled by setting the bridge protocol-mode=none, see https://wiki.mikrotik.com/wiki/Manual:L ... _addresses