If anyone is wondering: Heck with these labs teaching things like routing and BGP by just plugging routers together. I'm probably going to end up building a scale internet model (if I can) with all the layers and working parts and O̶̩̐̊h̴͉́̉ ̶͍͔͙͛́̓g̴͓͕̟̍o̸̩͆̌ͅd̶̡͇̰̍̃͌ ̶̳̈́̐͑h̵̨̯̃̑e̷̢͙̳̓̃̕l̴̨̳̃̓͂p̸͚̼̍̍ ̵̘͉̇̇m̴͙̟͙̽̓e̶͈͇̋́ ̵̢͔̏̌̀p̴̺̗̗̌ļ̶͍̿ĕ̵̪ȧ̴̡̯͍s̴̲̞̎e̵͕̦̽.
Currently, both AS30036 and AS13335 are BGP peers with the IXP acting as a transparent route server (so even though that's the gateway of last resort for both ASBRs, nobody cares about it for routing). AS30036 redistributes OSPF external type-2 routes to BGP (aka, consumer routes), and redistributes BGP routes to OSPF as type-1. Only has OSPF area 0 for now, thigh as I expand them they might go to IS-IS.
Solution: NSSA. a Not-So-Stubby Area seems to be the combination I'm looking for. ASBRs are still, well, accepted, and can send their routes to the ABR, and the ABR acts as a gateway for the entire area. Ergo, the PE router itself (ASBR) doesn't need an entire copy of the routing table, it just sends anything from the CE to the ABR, and that can figure out the correct path across the backbone to the other ASBR with a connection to the destination AS.
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