We've got a problem that's really got us stumped.
First off here's our setup:
Windows Server 2008
ESX 4.0 and ESXi 5.0 on vCenter 5
Trunked network cards on the backup server
Procurve 3500 network switch
Here's the problem:
When attempting a VMCopy job from ESX4 to ESXi5, the copy speed initially starts at 750Mbits. That's great.
However, about halfway along the way (sometimes even sooner), the copy stalls, and instead of progressing as it should, it starts broadcasting like crazy on our network.
Our whole network is slowed down when this happens!
The same thing happens when we attempt a VM restoratioon from ESX (4) to ESXi (5).
This problem has arisen ever since we upgraded our vCenter and ESXi to versions 5...
And it's driving us crazy

Any help would be appreciated!
Sorry if certain points are not as clear as they should be; I'll gladly provide details if necessary.
Olivier