cbtransfer does not work if there is an ephemeral bucket

Problem
When cbtransfer is execute when there is a ephemeral the following happens:

error: no vbucket_states in files: /opt/couchbase/var/lib/couchbase/data/cache/ 

There are two issues:

• cbtransfer is incorrect looking at bucket it has not been asked to
• cbtransfer does not work when there is a ephemeral bucket

Steps to reproduce

• Setup two one node clusters with just the Data Service.
• On cluster A:
  • Create a ephemeral bucket called cache
  • Load beer-sample
• On cluster B:
  • Create a new empty bucket called beer-sample
• On cluster a run cbtransfer:

/opt/couchbase/bin/cbtransfer couchstore-files:///opt/couchbase/var/lib/couchbase/data http://10.65.13.28:8091 -u Administrator -p Administrator -b beer-sample -B beer-sample                                                                    

error: no vbucket_states in files: /opt/couchbase/var/lib/couchbase/data/cache/ 

Workaround
If the cluster is down move the ephemeral bucket out of the way.

If the cluster is up-and-running, create a new temporary data directory (e.g. data-temp) then create symbolic links for all the buckets that are being extracted (e.g. the non-ephemeral buckets) into this temporary data directory then re-run the command.

If neither of these solutions are suitable, the 'cbdatarecovery' binary may be used, although please take note that this won't work in 7.1.0 due to MB-52445.