When a node installs, it may not have it's node mapped address up,
or may not have one at all. Try to use the ip if it would be in the
same set that produced it's ssh certificate.
There remains a gap if a system has no static addressing *and* doesn't
map nodename to IP, but we have an impasse as the situation is too fuzzy
to grant a prinicpal in an SSH cert, and without that we can't securely
attempt rsync. For now, this scenario would still fail and I will
just hope that doesn't come up.
