Hi.Good day.on N9K-93180YC-EX that running latest NX-OS (both 7.0.3.I7.8 / 7.0.3.I7.9) netflow failed to track INTRA-VLAN (Unicast traffic Within a VLAN) .my network is a simple Layer-2 fabric (VLAN only) with VPC and FEX . there is no L3/SVI/VRF and just a traditional old school L2 Fabric. I can see the flow that goes to L3 broadcast address x.x.x.255 and flows passing the LAG to the L3-Core.it look like some INTRA-VLAN unicast flow collection failed for unknown reason .maybe after changing some config in the devices. But maybe ! as we don't have too much change in config. The work around for me was just shut/no-shut VLAN (layer-2 VLAN) and everything work fine for an unexpected amount of time .i also find the last failure was due to upgrade the NX-OS and only 2 VLAN among of those 20 VLAN failed to collect the INTRA-VLAN (unicast traffic) flows and others work properly. I also find that when i send traffic to L3-Broadcast Address (ping x.x.x.255) FNF show me that flows but unicast communication between hosts in the same VLAN not collected (i checked both on flow collector and switch FNF local cache).also each time one or two different VLAN cashed from previous crash.Our network is too small that i am sure we are not reaching the FNF hardware limit in the ASIC.
