Believe it or not, but it seems that it is possible to crash a clean ESXi 5.5 host right out of the box by installing a Windows Server 2012 R2 virtual machine with an E1000 virtual network adapter and attempting a file copy to another VM located on the same box.
I was trying recently to copy some data from a Windows Server 2003 VM onto a new 2012 R2 VM on the same host. Expecting that the file copy should be extremely fast (due to proximity of network traffic on the same switch) I was left scratching my head when I noticed only 3-10MB/s transfer rate.
Because I was still running ESXi5.0 I thought it would be better to troubleshoot if I upgraded to the latest version of the hypervisor, only to find that the second I hit ‘paste’ to begin the file transfer the entire hypervisor crashed with a purple screen.
Needless to say, this isn’t a fringe case and others would appear to have noticed this behaviour too. The fix is simple enough, just swap out your E1000 vNIC on the 2012 R2 server with a vmxnet3 adaptor, but how is this simple scenario so dangerous that it is able to take out a whole host?
Thankfully, after swapping the vNIC I was then able to achieve 50-60MB/s throughput continuously, which was more than enough of an improvement given where I started before.
I’m going to link to the original post I found here, but nevertheless I’ll update this page if I find that there is a known issue somewhere that explains how this behaviour has occurred.