Yeah, having tried to raise this in a ticket just now, they're not going to fix this bug because they consider that this behaviour, and their incorrect interpretation of the word "originate", is
by design.
I suggested that if this was really intended behaviour that they should update their documentation to make this clear, but they avoided addressing the fact that this behaviour is both unusual compared to other vendors
and undocumented and instead decided to claim that the (also largely undocumented*) route selection filter feature could be used to restrict exactly
which defaults would be advertised.
So, here, for the benefit of anyone else who might come across this issue, the warning I would put in the documentation:
⚠ RouterOS does not advertise installed default routes under any circumstances unless the “default-originate” function is used (either “always” or “if-installed”), and when “if-installed” is used, RouterOS will disregard any “redistribute” settings for that peer/protocol where the default route is concerned and will advertise the existence of any default route learned from any protocol (in the relevant VRF).
RouterOS may not update the advertised default route to properly reflect the local active default route if it changes.
This is intended behaviour. ⚠
* See
https://help.mikrotik.com/docs/display/ ... eSelection for the not exactly comprehensive documentation on route select filters
