TS Lab 1 Ticket 4 (spoiler)

Anyone found the solution provided for ticket 4 is not complete? I'm not entirely sure how to complete it without setting a metric.

The provided solution says to bypass R7 via remove the redistribution of external routes on R7 via "area 50 nssa no-redistribution", and to remove the static null route invalidating the FA of

This is fine, except that the route to from R6 is ECMP from R9's point of view. Hence, half the packets willl still traverse the R7-R9 link which invokes the service-policy that drops all traffic. Note the below output is E1 because I was messing around trying E1 vs E2 which works similarly to forcing R7 to no-redistribution except same result of giving R9 an ECMP route to

R9#sh ip route
Routing entry for
  Known via "ospfv3 50", distance 110, metric 21
  Tag 101, type NSSA extern 1
  Last update from on GigabitEthernet1.79, 00:00:00 ago
  Routing Descriptor Blocks:
  *, from, 00:00:00 ago, via GigabitEthernet1.89
      Route metric is 21, traffic share count is 1
      Route tag 101, from, 00:00:00 ago, via GigabitEthernet1.79
      Route metric is 21, traffic share count is 1
      Route tag 101

An easy solution is to set the metric on the R7-R9 link or shut it lol (works fine either way) but that is not allowed within the restrictions. Given that the entire topology uses loopbacks and PBR/tunnelling is not allowed - how can you make that route NOT ECMP?


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