With Windows Server 2016 in a VM, my ping is 97ms and I get 2.39mbps download. On the host, ping is 7ms, and I get 29.95mbps download. I have a Windows 8.1 and a Windows 10 VM and they do not perform like that; I tried bridged and shared networking.. no difference.
Hi ThomasD1, More often than not, the network performance problems are the result of a Windows security feature. By default, Windows Server 2012 and 2012 R2 digitally sign SMB packets. This digital signature helps to protect against spoofing, but it adds some overhead to the traffic stream. You can get rid of this overhead and improve performance by disabling the SMB packet signing feature. You can disable it under Windows 2016 Server Group Policy Management Editor.
I did more tests with network speed - Host speed: good - VM Win 8: good - VM Win 10: good - VM Win Server 2012 R2: good - VM1 Win Server 2016: upload good, download abysmal - VM2 Win Server 2016: upload good, download abysmal - Native Win Server 2016 (on a PC): good As I created a new Win Server 2016 VM for testing, and tried other versions of the OS, and confirmed Win Server 2016 works properly on a PC, we can only conclude there is a specific issue with Win Server 2016 and Parallels. The different network modes don't make a different, and there is no VMQ setting in the virtual network adapter. The speed between the host and the VM is good between shared folders; the upload speed from the VM is good, so it is specifically the download that doesn't work well. There is nothing in the event log.
