Error configuring mongodb replicaset with inmemory I'm trying to configure a MongoDB replicaset with 3 replicas. The primary and another use the in memory storage engine, and the third uses wired tiger. I am using this configuration.

When I restart the cluster the data does not persist.

Server has startup warnings:

** WARNING: This replica set node is running without journaling enabled but the
**          writeConcernMajorityJournalDefault option to the replica set config
**          is set to true. The writeConcernMajorityJournalDefault
**          option to the replica set config must be set to false
**          or w:majority write concerns will never complete.
**          In addition, this node's memory consumption may increase until all
**          available free RAM is exhausted.


** WARNING: This replica set node is using in-memory (ephemeral) storage with the
**          writeConcernMajorityJournalDefault option to the replica set config
**          set to true. The writeConcernMajorityJournalDefault option to the
**          replica set config must be set to false
**          or w:majority write concerns will never complete.
**          In addition, this node's memory consumption may increase until all
**          available free RAM is exhausted.


And my configuration.

rs0:PRIMARY&gt; cfg = rs.conf()
{
        "_id" : "rs0",
        "version" : 102744,
        "protocolVersion" : NumberLong(1),
        "writeConcernMajorityJournalDefault" : false,
        "members" : [
                {
                        "_id" : 0,
                        "host" : "mongodb-mongodb-replicaset-0.mongodb-mongodb-replicaset.default.svc.cluster.local:27017",
                        "arbiterOnly" : false,
                        "buildIndexes" : true,
                        "hidden" : false,
                        "priority" : 1,
                        "tags" : {

                        },
                        "slaveDelay" : NumberLong(0),
                        "votes" : 1
                },
                {
                        "_id" : 1,
                        "host" : "mongodb-mongodb-replicaset-1.mongodb-mongodb-replicaset.default.svc.cluster.local:27017",
                        "arbiterOnly" : false,
                        "buildIndexes" : true,
                        "hidden" : false,
                        "priority" : 1,
                        "tags" : {

                        },
                        "slaveDelay" : NumberLong(0),
                        "votes" : 1
                },
                {
                        "_id" : 2,
                        "host" : "mongodb-mongodb-replicaset-2.mongodb-mongodb-replicaset.default.svc.cluster.local:27017",
                        "arbiterOnly" : false,
                        "buildIndexes" : true,
                        "hidden" : true,
                        "priority" : 0,
                        "tags" : {

                        },
                        "slaveDelay" : NumberLong(0),
                        "votes" : 1
                }
        ],
        "settings" : {
                "chainingAllowed" : true,
                "heartbeatIntervalMillis" : 2000,
                "heartbeatTimeoutSecs" : 10,
                "electionTimeoutMillis" : 10000,
                "catchUpTimeoutMillis" : -1,
                "catchUpTakeoverDelayMillis" : 30000,
                "getLastErrorModes" : {

                },
                "getLastErrorDefaults" : {
                        "w" : 1,
                        "wtimeout" : 0
                },
                "replicaSetId" : ObjectId("5e736baa5c51ff3e198dd880")
        }
}


The writeConcernMajorityJournalDefault option IS set to false!

Thanks in advance!
Ok what you need to do is to change:

    mongo "${ssl_args[@]}" --eval "rs.initiate({'_id': '$replica_set', 'members': [{'_id': 0, 'host': '$service_name'}]})"


to

    mongo "${ssl_args[@]}" --eval "rs.initiate({'_id': '$replica_set', 'writeConcernMajorityJournalDefault': false, 'members': [{'_id': 0, 'host': '$service_name'}]})"


The data still doesn't persist.