HDFS - Consolidate 2 small volumes into 1 large volume

[Brian C. Huffman]

All,

Is it possible to consolidate two small data volumes (500GB each) into a 
larger data volume (3TB)?

I'm thinking that as long as the block file names and metadata are 
unique, then I should be able to shut down the datanode and use 
something like tar or rsync to copy the contents of each small volume to 
the large volume.  Will that work?

Thanks,
Brian