# Driver doesn't validate maxStalenessSeconds for mongos --- heartbeatFrequencyMS: 10000 topology_description: type: Sharded servers: - &1 address: a:27017 type: Mongos avg_rtt_ms: 5 lastUpdateTime: 0 maxWireVersion: 6 lastWrite: {lastWriteDate: {$numberLong: "1"}} - &2 address: b:27017 type: Mongos avg_rtt_ms: 50 # Too far. lastUpdateTime: 0 maxWireVersion: 6 lastWrite: {lastWriteDate: {$numberLong: "1"}} read_preference: mode: Nearest maxStalenessSeconds: 1 # OK for sharding. suitable_servers: - *1 - *2 in_latency_window: - *1