1topology_description: 2 type: ReplicaSetNoPrimary 3 servers: 4 - &1 5 address: b:27017 6 avg_rtt_ms: 5 7 type: RSSecondary 8 tags: 9 data_center: nyc 10 - &2 11 address: c:27017 12 avg_rtt_ms: 100 13 type: RSSecondary 14 tags: 15 data_center: nyc 16operation: read 17read_preference: 18 mode: PrimaryPreferred 19 tag_sets: 20 - {} 21suitable_servers: 22- *1 23- *2 24in_latency_window: 25- *1