# maxStalenessSeconds is applied before tag sets. With tag sets
# [{data_center: nyc}, {data_center: tokyo}], if the only node in NYC is stale
# then use Tokyo.
---
heartbeatFrequencyMS: 25000  # 25 seconds.
topology_description:
  type: ReplicaSetWithPrimary
  servers:
  - &1
    address: a:27017
    type: RSPrimary
    avg_rtt_ms: 5
    lastUpdateTime: 0
    lastWrite: {lastWriteDate: {$numberLong: "125002"}}
    maxWireVersion: 5
    tags:
      data_center: tokyo
  - &2
    address: b:27017
    type: RSSecondary
    avg_rtt_ms: 5
    lastUpdateTime: 0
    lastWrite: {lastWriteDate: {$numberLong: "1"}}  # Too stale.
    maxWireVersion: 5
    tags:
      data_center: nyc
read_preference:
  mode: Nearest
  maxStalenessSeconds: 150
  tag_sets:
  - data_center: nyc
  - data_center: tokyo
suitable_servers:
- *1
in_latency_window:
- *1