This unresolved issue: https://github.com/projectatomic/adb-atomic-developer-bundle/issues/272

Is causing rsync issues such as:

default: Rsyncing folder: /c/DeveloperPlatform/cdk/components/rhel/rhel-ose/ => /vagrant
There was an error when attempting to rsync a synced folder.
Please inspect the error message below for more info.

Host path: /c/DeveloperPlatform/cdk/components/rhel/rhel-ose/
Guest path: /vagrant
Command: rsync --verbose --archive --delete -z --copy-links --chmod=ugo=rwX --no-perms --no-owner --no-group --rsync-path sudo rsync -e ssh -p 2222 -o StrictHostKeyChecking=no -o IdentitiesOnly=true -o UserKnownHostsFile=/dev/null -i 'C:/DeveloperPlatform/cdk/components/rhel/rhel-ose/.vagrant/machines/default/virtualbox/private_key' --exclude .vagrant/ /c/DeveloperPlatform/cdk/components/rhel/rhel-ose/ vagrant@127.0.0.1:/vagrant
Error: Warning: Permanently added '[127.0.0.1]:2222' (ECDSA) to the list of known hosts.

dup() in/out/err failed

rsync: connection unexpectedly closed (0 bytes received so far) [sender]
rsync error: error in rsync protocol data stream (code 12) at io.c(226) [sender=3.1.2]