Hope this helps a little with the issue, as Andre says, the answer for my case was in the worker logs, and all have to do with the DNS, here's the tip:
In your Host file, ensure that you have this:
* IP and Hostname from the source
* IP and hostname of the vCenter
* IP and hostname of the master host**
Dunno but this last one was the clue to get off the I/O error, doesn't matter if it's a farm or a cluster, try it!