I think the problem is unique to situations where you have link aggregation to the core switch.  I've seen a few other posts online about this issue, and all have AGGR/XYZ ports showing for the client. ... View more

We have the same exact problem, and it's really annoying.  Most of our clients are showing our core switch (a Meraki layer 3 we have configured as our core switch) which seems to be the same setup as OP.  We also have our IDF switches all connected with LACP link aggregation which you seem to also have setup.  I opened a case about this issue but have not received any response in over 5 days now.   The documentation is pretty clear that unique client identifier is the correct option for all Meraki networks.  If we switch to track my MAC the MX is not going to be able to see any of the IPs of the clients on the core switch. ... View more