Hsflowd v2.1.11-5 has a working mod_vpp, but the master branch has a fix to the iftype and ifdirection fields that are exported in the sflow counters for vpp interfaces. We expect to tag a v2.1.12-1 release soon that will include this fix. Let me know if there is a deadline and you need it right away.

hsflowd expects the agent-address to be chosen from addresses it can see in it's own namespace.

I think the PPP interface will be recognized if hsflowd knows the MAC address (FEAA9ADDF555) belongs to it. That MAC address is supposed to be learned when the interfaces are read here:

Yes. Packet drops are classed as "event_samples" internally. Definitions for telemetry counters are here:
https://github.com/sflow/host-sflow/blob/v2.0.50-4/src/Linux/hsflowd.h#L460-L486

The packet-drop events are not really samples in the same way as the packets are random-samples and the counters are time-samples. Even if there is only 1 dropped packet it will be sent. So it might be better to change the wording from “Samples drop events sent” to something like “Packet drop events sent” or just “Packet drops sent”. Make sense?

Apologies. I believe it is corrected now.

I think there should be one more metric - the number of packet-drop-events sent. I just checked in a change that adds to the example telemetry.py script:
https://github.com/sflow/host-sflow/commit/5b01779abf21a7553e07188ff2f54850c568f786

Starting in hsflowd version 2.0.50-3, the mod_dbus module can be asked for the current sFlow agent-address along with other stats, and the example "telemetry" and "telemetry.py" scripts in the repo under src/Linux/scripts/ have both been updated. So if you wanted to offer a "show sflow" CLI command then you might adapt one or other of those scripts to extract the information from the running hsflowd process. The steps would be: