R5:router ospf 1area 3 nssa default-information-originatearea 3 default-cost 500
R5:router ospf 1area 3 nssa default-information-originate metric 500
I don't understand how R8 can reply to pings with no route to R6 loopback (before advertising the default)?
I can ping R8 loopback from R6, but not R6 from R8. I would think that communication would be broke both ways?
I also used the alternate one line config using "metric 500" and it seems to produce the same results as "default-cost 500" Is there a situation where one would be used over the other or would either be acceptable?
I think what you will find is that the default-cost 500 will apply that default-cost to any routes redistributed into the NSSA, whereas applying the metric will just apply it to the default. I havent labbed this though so cant confirm.