collectd.log (in debug) reports that data collection is run and being persisted:

2012-04-10 10:12:11,022 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: collecting 192.168.1.27 on node ID 2
2012-04-10 10:12:11,034 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=ClassLoading, # attributes: 3, # composite attribute members: 0
2012-04-10 10:12:11,037 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=MemoryPool,name=Old Gen, # attributes: 3, # composite attribute members: 4
2012-04-10 10:12:11,038 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=GarbageCollector,name=Copy, # attributes: 3, # composite attribute members: 3
2012-04-10 10:12:11,039 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=GarbageCollector,name=ParNew, # attributes: 3, # composite attribute members: 3
2012-04-10 10:12:11,040 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=GarbageCollector,name=PS MarkSweep, # attributes: 3, # composite attribute members: 3
2012-04-10 10:12:11,040 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=Threading, # attributes: 4, # composite attribute members: 0
2012-04-10 10:12:11,041 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=MemoryPool,name=Perm Gen, # attributes: 3, # composite attribute members: 4
2012-04-10 10:12:11,043 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=GarbageCollector,name=PS Scavenge, # attributes: 3, # composite attribute members: 3
2012-04-10 10:12:11,044 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=MemoryPool,name=Survivor Space, # attributes: 4, # composite attribute members: 8
2012-04-10 10:12:11,045 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=GarbageCollector,name=MarkSweepCompact, # attributes: 3, # composite attribute members: 3
2012-04-10 10:12:11,046 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=MemoryPool,name=Eden Space, # attributes: 4, # composite attribute members: 8
2012-04-10 10:12:11,047 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: OpenNMS:Name=Queued, # attributes: 11, # composite attribute members: 0
2012-04-10 10:12:11,048 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=OperatingSystem, # attributes: 4, # composite attribute members: 0
2012-04-10 10:12:11,049 DEBUG [CollectdScheduler-50 Pool-fiber1] Jsr160Collector: jsr160 Collector - getAttributes: java.lang:type=GarbageCollector,name=ConcurrentMarkSweep, # attributes: 3, # composite attribute members: 3
2012-04-10 10:12:11,051 INFO [CollectdScheduler-50 Pool-fiber1] OneToOnePersister: Persisting data for resource node[2]

however, no file is being created (note, this is the one-to-one persister).

the following may (or may not) help pinpoint the problem:

2012-04-10 10:12:05,402 DEBUG [CollectdScheduler-50 Pool-fiber0] ThresholdingSet: getThresholdGroupNames: address/service: 192.168.1.27/JSR160-9103 not scheduled, service is not enabled or does not exist in package: mib2
2012-04-10 10:12:05,402 DEBUG [CollectdScheduler-50 Pool-fiber0] ThresholdingSet: getThresholdGroupNames: address/service: 192.168.1.27/JSR160-9103 not scheduled, service is not enabled or does not exist in package: hrstorage
2012-04-10 10:12:05,402 DEBUG [CollectdScheduler-50 Pool-fiber0] ThresholdingSet: getThresholdGroupNames: address/service: 192.168.1.27/JSR160-9103 not scheduled, service is not enabled or does not exist in package: cisco
2012-04-10 10:12:05,402 DEBUG [CollectdScheduler-50 Pool-fiber0] ThresholdingSet: getThresholdGroupNames: address/service: 192.168.1.27/JSR160-9103 not scheduled, service is not enabled or does not exist in package: netsnmp
2012-04-10 10:12:05,402 DEBUG [CollectdScheduler-50 Pool-fiber0] ThresholdingSet: getThresholdGroupNames: address/service: 192.168.1.27/JSR160-9103 not scheduled, service is not enabled or does not exist in package: netsnmp-memory-linux
2012-04-10 10:12:05,402 DEBUG [CollectdScheduler-50 Pool-fiber0] ThresholdingSet: getThresholdGroupNames: address/service: 192.168.1.27/JSR160-9103 not scheduled, service is not enabled or does not exist in package: netsnmp-memory-nonlinux

I have not attached the collectd/datacollection definition because apparently they are okay since data collection does happen - let me know if you need it. the problem relates to the error reporting as much as to the actual problem (i'd like to know what's going on, not just get the data collected)