Unfortunately, at this point, sFlow is something that our VIRL lab devices do not support (not even with the NX-OSv virtual switches). You can either use a Cisco Nexus 3000 switch or other vendor switches, such as Arista, that support sFlow. Another good option for the lab is to use an Arista vEOS virtual instance. I happen to have access to a Cisco Nexus 3048 switch running 7.0 (3), which I will be using for this section as the sFlow exporter.
The configuration of Cisco Nexus 3000 for sFlow is straightforward:
Nexus-2# sh run | i sflowfeature sflowsflow max-sampled-size 256sflow counter-poll-interval 10sflow collector-ip 192.168.199.185 vrf managementsflow agent-ip 192.168.199.148sflow data-source interface ...
