Hello Alex,   
      
   On Tuesday January 23 2018 15:48, you wrote to me:   
      
    AS>>>>> ipv6.dynamic.ziggo.nl [2001:1c02:1100:d700:f1d0:2:280:5555]   
    AS>>>>> but your ISP does not seem to assign proper reverse DNS for   
    AS>>>>> customers.   
    MvdV>>>> Indeed, that is a bit of a joke. Every IPv6 addres   
    MvdV>>>> (2001:1c02::/32) of my provider backresolves to   
    MvdV>>>> ipv6.dynamic.ziggo.nl.   
    AS>>> Is it dynamic or static?   
    MvdV>> Dynamic.   
      
    AS> So it is set automatically by ISP and changes every time you   
    AS> reconnect? Then how did you set it to f1d0-style?   
      
   No, they call it dynamic, because they do not guarantee that the /56 prefix   
   will never change. Since November 2017 it has only changed once. That was   
   after a three hour unscheduled power down. Short power interuptions do not   
   seem to cause a change.   
      
   Even so, all THEY set is the prefix. Within the /64, I can either use SLAAC or   
   configure it manually. The latter I did for the ::f1d0:2:280:5555 part.   
      
      
   Cheers, Michiel   
      
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