I'm a little worried about the missing cleanup. Today, there was a question about the hourly PTR requests (on a dutch forum), visible in the query log. The user indicated he was already seeing about 90 PTR request on the hour, I assume this is due to the windows 10 privacy extensions and the ever changing IPv6 temporary address. I have no problem writing a cleanup routine myself, the average user will NOT (be able to) do this. Further more I use the MAXDBDAYS=8 setting, which makes cleanup relatively easy (the databse remains relatively small), as you already indicated, most users will NOT use this setting and have the default 365 days history.
Apart from this, letting you know that everything works as expected, no more IPv6 addresses without a name. Thank you for this.
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even works perfect for a Raspbian client with enabled privacy extensions, read here
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