Re: IPv6 routing /48s

[Perry Lorier]

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).  :(