The judge's tests run against files and fakes; the drill runs it against a
real resolver file and real resolvers, rewritten as the VPN client does,
and records the statements the controller's replay raises and clears from.
A VPN client rewrote the laptop's resolver file and every mesh name failed
while each module read healthy: nothing asked the machine. The engine now
looks every 30 s at the resolver file the uplink holder declared (naming
the program that rewrote it), the names through each listed resolver
(NXDOMAIN for a mesh name's IPv6 address is a finding, issue 262), the
tunnel's handshake with the hub, the bus and the default route; a part is
unhealthy on its second failing look, and the statement carries it.