Why is Unbound not like a `dig +trace`?

[François Lafont]

After some searches I think I have the answer.

According to the RFC 1034 (maybe in 5.3.3), nothing forces a recursive DNS resolver to behave like a `dig +trace`, end of story.
Is that about right?

At least I have learned how to compile unbound from source and run it in a docker. :)

Bye.

-- 
François Lafont