It seems that there is a problem when a replica set mixes nodes on version 3.2 and 3.4. If one of the 3.4 is used to initialize the replica set, it stores a BsonDecimal somewhere. It cannot be replicated to nodes on version 3.2 and eventually they die because of that. It is an error on mongodb, but our library should be able to deal with it:
It should prevent this kind of configurations
It should detect that a node on the replica set has die, and react properly (for example, killing whole replica set). This is important because when some of the nodes dies, mongo clients will have deadlocs/timeouts when trying to execute commands with total write concern.
It seems that there is a problem when a replica set mixes nodes on version 3.2 and 3.4. If one of the 3.4 is used to initialize the replica set, it stores a BsonDecimal somewhere. It cannot be replicated to nodes on version 3.2 and eventually they die because of that. It is an error on mongodb, but our library should be able to deal with it: