Question about additional section in BIND-responses

[Tom]

On 8/17/22 06:45, Tom wrote:
> 
> 
> On 8/17/22 02:27, Evan Hunt wrote:
>> On Tue, Aug 16, 2022 at 05:28:19PM +0200, Tom wrote:
>>> Using BIND-9.18.5 as a recursive server:
>>> What's the reason, that BIND answers with the additional section for the
>>> the following query where for example Knot resolver and also PowerDNS
>>> resolver doesn't add the additional section for the same query?
>>>
>>> [...]
>>>
>>> Any hints why BIND adds the additional section while other resolvers
>>> doesn't? Is there an option in BIND to behave like Knot/PDNS?
>>
>> The option is "minimal-responses".  If you set it to "yes", it will omit
>> authority and additional section data except when necessary.
>>
>> The default is "no-auth-recursive", which omits authority section data
>> when it isn't strictly necessary, but will still add additional data for
>> records in the answer section.
>>
> 
> I've already set "minimal-responses yes;", but the additional 
> section/data is still shown. So based on your explanation, BIND assumes, 
> this data is necessary, why? And why behaves BIND different here than 
> Knot/PDNS where no additional section is shown for the same query?

Does an BIND expert has an idea or an explanation, why the additional 
section is still shown, although "minimal-responses yes;" is set? And 
why the additional section seems necessary for BIND and not for example 
for Knot/PDNS for the same query?

Many thanks for any hints.
Tom