In a sharded / replica set environment, map/reduce output data are not written in secondary nodes :

I have 9 nodes (6 nodes + 3 arbiters) shared between 3 replica sets (rs1, rs2, rs3). My map/reduce operation process a sharded collection, and write output result in a normal collection (non-sharded).

As result, I have my output collection created in primay and secondary node, but only primary node contains data.

I didn't found any information in logs..

I can show you replication status :

PRIMARY> db.count_dm_4f6aef18d4ee7771b1a591e6.find(); // Returns my element

{ "_id" : "4f6aef18d4ee7771b1a591e6", "value" : 453 }

PRIMARY> db.printReplicationInfo()
configured oplog size: 6966.868750000001MB
log length start to end: 85347secs (23.71hrs)
oplog first event time: Wed Mar 21 2012 11:21:07 GMT+0100 (CET)
oplog last event time: Thu Mar 22 2012 11:03:34 GMT+0100 (CET)
now: Thu Mar 22 2012 11:03:35 GMT+0100 (CET)

SECONDARY> db.count_dm_4f6aef18d4ee7771b1a591e6.find(); // Returns nothing ...
SECONDARY> db.printReplicationInfo()
configured oplog size: 6792.466796875MB
log length start to end: 85358secs (23.71hrs)
oplog first event time: Wed Mar 21 2012 11:21:07 GMT+0100 (CET)
oplog last event time: Thu Mar 22 2012 11:03:45 GMT+0100 (CET)
now: Thu Mar 22 2012 11:03:46 GMT+0100 (CET)