Feb 06 20:19:43 dns02 kresd[24857]: error:
/usr/lib/knot-resolver/predict.lua:34: 'struct
rr_type' has no member named 'nil'
[...]
Is it related to setting reorder_RR (true)?
Is this a configuration issue in this case? Or is it a
known bug?
It's not known, and it's most likely unrelated to reorder_RR. I
expect it's some edge case not handled well in predict.lua, though I
can't immediately see how the error might happen.