1. Start a sharded cluster on one of the latest MongoDB releases (i.e. 7.0.5, 6.0.12 - older releases also seem to exhibit this behavior from checking a couple others) 2. Enable sharding sh.enableSharding( "timeseries" ); sh.shardCollection( "timeseries.weather" , { "metadata.sensorId" : 1 }, { timeseries: { timeField: "timestamp" , metaField: "metadata" , granularity: "hours" } } ); 3. Insert a few sample docs   db.getSiblingDB( "timeseries" ).weather.insertMany([ { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-18T00:00:00.000Z" ), "temp" : 12 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-18T04:00:00.000Z" ), "temp" : 11 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-18T08:00:00.000Z" ), "temp" : 11 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-18T12:00:00.000Z" ), "temp" : 12 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-18T16:00:00.000Z" ), "temp" : 16 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-18T20:00:00.000Z" ), "temp" : 15 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-19T00:00:00.000Z" ), "temp" : 13 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-19T04:00:00.000Z" ), "temp" : 12 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-19T08:00:00.000Z" ), "temp" : 11 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-19T12:00:00.000Z" ), "temp" : 12 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-19T16:00:00.000Z" ), "temp" : 17 }, { "metadata" : { "sensorId" : 5578, "type" : "temperature" }, "timestamp" : ISODate( "2021-05-19T20:00:00.000Z" ), "temp" : 12 }] ); 4. Attempt to query the sharded timeseries collection in some way specifying readConcern: "available" and the operation will hang indefinitely.  Any other readConcern level seems to work fine.     db.getSiblingDB( "timeseries" ).weather.find({ "metadata.sensorId" : 5578}).readConcern( "available" ); db.getSiblingDB( "timeseries" ).weather.find().readConcern( "available" ); db.getSiblingDB( "timeseries" ).weather.count({},{readConcern: "available" });