Thanks Alex,
was kind of suspectig we where running up against limitations in OSPF, was hoping we could just get this doing what we want but may need to seriosuly think about moving onto a more extensible solution.
i found this cisco blog quite useful in helping me understand whats going on here
https://cciethebeginning.wordpress.com/2015/01/21/ospf-inter-area-and-intra-area-routing-rules/#
My big question now is trying to understand why a route will choose area 300 instead of area 0 when there has been no declaration for the route to be in any area. As i understand it, a direct interface route would be in the router LSA and advertised across both area 0 and area 300, so why is area 300 chosen? is it because there is a preference to route across non area 0 (non backbone) if there is a choice of both?
is there a list somewhere of the heirachy of decision making.
if i undretsand this correctly, is it impossible to designate a route in an area and maintain tagging? we must just let the protocol advertise to all areas and make its own a choice, which we are unable to influence, to which ospf area it will decide to route across if we ant to tag?
Thanks again.