Rehearsed on three lab machines before doing it on an anchor: loading the mesh's
rules refuses an ordinary host port and leaves a published container port
reachable, same prober, same second.
It is deliberate — no forward chain, because dropping there would stop every
container — but traffic to a published port never reaches the input chain, so
the firewall is silent about it. The anchor publishes 38 such ports today, all
filtered by the system being replaced, so the cutover would open every one of
them while reporting a firewall that is up.
jschoubben