Got slow network backup with windows 8.1 to managed vaults? I just fixed mine!
I was getting 1.5 to 2Mbytes a sec backing up to a managed vault on a storage node over a 1G wireless network. An unmnaged vault on the same storage node would backup at 30Mbytes a sec.
By making quite a few changes on the storage node server and the client in the tcp settings I was able to get both managed and unmanaged running at 30Mbytes sec.
I finally found the issue tonight after a few hours or trial and error with a lot of TCP settings.
I had to change quite a few windows 8.1 TCP settings and add a couple of tuning parameters that have been taken away on windows 8.1
I changed Tcp1323Opts to =3 (from 2)
I added TcpWindowSize =131400
I added DisableTaskOffload =1
I added Disable LargeMtu=0
I now get 30Mbytes sec using both managed and unmanged vaults.
I used a TCP optimizer to maximize the TCP receive window and turned on TCP 1323 options with timestamps.
I also turned on ctcp with set global congestionprovider=ctcp which doesn’t exist normally in windows 8.
I also had to make the following registry change for the ctcp to work.
------------
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Nsi\{eb004a03-9b1a-11d4-9123-0050047759bc}\0]
"0200"=hex:00,00,00,00,01,00,00,07,00,00,00,00,00,00,00,00,1e,00,00,00,00,00,\
00,00,00,00,00,00,02,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,ff,\
00,ff,00,ff,ff,00,00,00,00,00,00,00,00,ff,ff,ff,ff,00,00,00,00,00,00,00,00,\
ff,ff,00,00,ff,ff,ff,ff,00,00,00,00,00,00,00,00
"1700"=hex:00,00,00,00,01,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\
00,00,00,00,00,00,02,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\
00,ff,00,ff,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\
ff,00,00,00,ff,ff,ff,ff,00,00,00,00,00,00,00,00
--------------
I also set netsh int tcp set global autotuninglevel=experimental (restricted also worked)
I also disabled offloading with the settings in the registry above.
Hope this helps someone else!
