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# By default, a read preference sets no maximum on staleness.
---
topology_description:
  type: ReplicaSetWithPrimary
  servers:
  - &1
    address: a:27017
    type: RSPrimary
    avg_rtt_ms: 50  # Too far.
    lastUpdateTime: 0
    maxWireVersion: 5
    lastWrite: {lastWriteDate: {$numberLong: "1000001"}}
  - &2
    address: b:27017
    type: RSSecondary
    avg_rtt_ms: 5
    lastUpdateTime: 0
    maxWireVersion: 5
    lastWrite: {lastWriteDate: {$numberLong: "1"}}  # Very stale.
read_preference:
  mode: Nearest
suitable_servers:  # Very stale server is fine.
- *1
- *2
in_latency_window:
- *2