I ran into the same problem yesterday.
Didn't really try to analyse it in detail, but it looked like it didn't set up the network correctly after the first boot. What I did to fix it was essentially uninstalling network-manager and configuring the interface instead in /etc/network/interfaces (as dhcp).
One other thing I noticed was that one script was failing because of a missing "iozone" test run (but not sure if that then caused the network configuration issue).