How to describe what stats are required, especially in the ICMP Msg table?
Require per-interface, per-system, both, some?  Require tracking every
ICMP message type or just the ones the system cares about?  What about
ICMP codes?

--- 8/8
no code
type: every
per-system in mandatory table/group
per-interface in separate optional table/group
    table DESCRIPTION: why useful?
    group DESCRIPTION: why optional
    comment out for now, can't find why useful