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# maxStalenessSeconds must be at least 90 seconds, even with no known servers.
---
topology_description:
  type: ReplicaSetNoPrimary
  servers:
  - &1
    address: a:27017
    type: Unknown
  - &2
    address: b:27017
    type: Unknown
read_preference:
  mode: Nearest
  maxStalenessSeconds: 1  # Too small.
error: true