Cbtransfer copying 0 documents

I want to copy one bucket from one server to another server in another machine using the cbtransfer as indicated here: https://developer.couchbase.com/documentation/server/3.x/admin/Tasks/backup-restore-tween-opsys.html

As the 8091 port on the remote server is not open I’m using a ssh tunnel and forwarding the local port.

This is the command that I’m using:
$ ./cbtransfer http://localhost:9000 http://localhost:8091 -b b1 -B b1 -u Administrator -p password -v

2017-05-05 19:17:40,391: w0 source : http://localhost:9000(b1@127.0.0.1:8091)
2017-05-05 19:17:40,391: w0 sink : http://localhost:8091(b1@127.0.0.1:8091)
2017-05-05 19:17:40,391: w0 : total | last | per sec
[ ] 0.0% (0/estimated 1498516 msgs)
bucket: b1, msgs transferred…
: total | last | per sec
batch : 0 | 0 | 0.0
byte : 0 | 0 | 0.0
msg : 0 | 0 | 0.0
done

Don’t know what’s going on. Any help? Thanks.