18 Nov
2008
18 Nov
'08
4:13 p.m.
Having no route is not a problem, you should get a destination unreachable directly and all is fine because IPv4 should be used as a fallback.
The big problem is when you have a route to them, but they don't have a route back. You don't get destination unreachables, but instead get timeouts, and pain, and misery (btdt). :(