For the initial release, you are right that you'll find most of these metrics in net-snmp. It's the selection that's more interesting, which is guided by the US

For the initial release, you are right that you'll find most of these metrics in net-snmp. It's the selection that's more interesting, which is guided by the USE method: identifying utilization, saturation, and error metrics for key resources. We're missing some metrics (so do all monitoring tools), and we'll be extending Vector to include them (as can other people, as it's open source). One challenge is that there are some metrics that the kernel doesn't make available, so we need to either use tracers to fetch them, patch the kernel, or use custom kernel modules. In recent weeks, I've been using (or trying to use): ftrace, perf_events, SystemTap, eBPF, and LTTng. I've also used others, but not in the last few weeks. I'm really looking forward to getting these advanced tools into Vector.