Can some of you please do me a favor? Find a VM of yours running on ESXi 5.1, preferably 1117900 and let me know if you are seeing Rx packet loss in the performance stats that vCenter provides. Every single VM in my environment is reporting packet loss. Virtual machines running on ESXi 5.0 are not reporting this at all. This is also not an issue at the host level as there is no noted packet loss there.