[dns-operations] DNS continuity during registrar transfers (was Re: Enom's name server broken?)

[Matthew Pounsett]

On 2013/01/15, at 09:41, Mark Jeftovic wrote:

> 
> 
> On 13-01-15 8:46 AM, Mark Andrews wrote:
>> 
>> For clean transfers of zones from one provider to the next the
>> losing provide should slave the zones from the new provider.  This
>> ensures that caches only see current content regardless of whether
>> they are talking to the new or old servers.
>> 
> 
> I think this almost never happens in the real world when domains move
> from one set of auth nameservers to another. What the losing servers can
> do is continue to serve the data they have, especially in the case of a
> registrar transfer because in a lot of cases the zone data will be the
> same for an overlapping period of time.

This almost never happens because cooperation between the two service providers is difficult to obtain.  Speaking as a service provider, I've managed to get inter-operator zone transfers happening post-transfer on a small number of occasions (from both sides of the transfer), but only because the customer was large enough to demand it of the other operator when we suggested it.  With smaller customers, and here speaking also as a customer on a few occasions, it's impossible to get both operators to care enough to do the extra work to open up zone transfers between the two organizations.  

So I think you're right.  In most cases, the only option for the losing operator is just to serve what they've got until the TTLs run out.