We've packaged our own chukwa rpms to be able to deploy the collector, the agent and the data processor each separately. In doing so I realized that the data processor (i.e., Demux) has a dependency on conf/chukwa-collector-conf.xml as packaged in the distro, since that's the only place where where 'writer.hdfs.filesystem' is set.
The workaround is straight forward enough (just add writer.hdfs.filesystem to chukwa-demux.xml), but I thought I'd point out the cross-dependency. Although it feels redundant, it seems the proper thing to do would be to include writer.hdfs.filesystem in both configs, since both processes have that dep. Thoughts?