I have a server running Server 2008 that is behaving veryodd in regards to networking speed. On all networkdownloads from the server, speeds are in the Gigabit range. On allnetwork uploads to the server, speeds are in the Megabit range. Interestingly, this machine isrunning Hyper-V, and the exact opposite is truewhen looking at the virtual machine instances running on the server. Network downloads from a virtual machine instance is slow, while network uploads to a virtual machine instance is very fast.What gives? My server is running a Supermicro motherboard (X7DCA-i)with dual E5440 (quad-core) Intel chips and 16 GB of RAM. I have tested using both the onboard Gigabit ports as well as an Intel Gigabit PCI-X Gigabitadd-in card. Additionally, I have tested network reads and writes to local RAIDed drives as well as drives provided through an iSCSI connection - the results are identical.Any ideas?

Hi,One idea is toadjuststep by step thefeatures that are available for the TCP/IP protocol in Windows Server 2008 and see the efects on the networking speeds. To see the status of the parameters, run in command line:netsh int tcp show globalHere is an article about some of these parameters:http://support.microsoft.com/kb/951037Have a nice day! The Masterplan - MCSE,MCITP-EA http://winmasterplan.blogspot.com

Thanks for the response, and good article. Unfortunately, I don't think this is my problem.I would expect my CPU to peak if it were, and CPU utilization stays minimal.Despite that,I looked into implemented the suggestions.RSS and NetDMA were already enabled, and TCP offloading does not work when Hyper-V is installed.To give some concrete numbers, I moved a 512 MB file from another server to the problem server - it completed in about 3 minutes. Transfering that same file from the problematic server to another server takes under 15 seconds. In other words, uploading to the problem server is very slow while dowloading from the server is very fast.Thinking this may be a problem with the virtual switch created in Hyper-V, I removed all virtual networks and uninstalled each of my network adapters. I then scanned for hardware changes and reset all of my adapter settings. Same result.Aside from Hyper-V, there is nothing else loaded on this server - it is an out of the box install. And since I took away all of the Hyper-V virtual networks, I think I have eliminated that as a possibility also. Any other suggestions would be appreciated.