Windows Server 2012 R2 and TCP slow start and Hyper-v hosts
I need to change default value of TCP InitialCongestionWindow
I read this document: https://www.iispeed.com/blog/windows-server-2012-and-tcp-slow-start
I tryed it on our hyper-v hosted virtual server 2012 R2.
PS C:\>Set-NetTCPSetting -SettingName Custom -InitialCongestionWindow 10 -CongestionProvider CTCP
I got error:
Set-NetTCPSetting : No MSFT_NetTCPSetting objects found with property 'SettingName' equal to 'Custom'. Verify the valu
e of the property and retry.
At line:1 char:1
+ Set-NetTCPSetting -SettingName Custom -InitialCongestionWindow 10 -CongestionPro ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (Custom:String) [Set-NetTCPSetting], CimJobException
+ FullyQualifiedErrorId : CmdletizationQuery_NotFound_SettingName,Set-NetTCPSetting
The question is how can I acomplish what that IISspeed document is telling about? If I Change this on Hyper-v machine Do i allso need change this on hypers-v host too to actualy make any difference?
Should I allso make the same change to SSL port 443 ?
I ran this command:
PS C:\Users\Administrator> Get-NetTCPSetting
SettingName : Automatic
MinRto(ms) :
InitialCongestionWindow(MSS) :
CongestionProvider :
CwndRestart :
DelayedAckTimeout(ms) :
DelayedAckFrequency :
MemoryPressureProtection :
AutoTuningLevelLocal :
AutoTuningLevelGroupPolicy :
AutoTuningLevelEffective :
EcnCapability :
Timestamps :
InitialRto(ms) :
ScalingHeuristics :
DynamicPortRangeStartPort :
DynamicPortRangeNumberOfPorts :
AutomaticUseCustom :
NonSackRttResiliency :
ForceWS :
MaxSynRetransmissions :
SettingName : InternetCustom
MinRto(ms) : 300
InitialCongestionWindow(MSS) : 4
CongestionProvider : CTCP
CwndRestart : False
DelayedAckTimeout(ms) : 50
DelayedAckFrequency : 2
MemoryPressureProtection : Enabled
AutoTuningLevelLocal : Normal
AutoTuningLevelGroupPolicy : NotConfigured
AutoTuningLevelEffective : Local
EcnCapability : Enabled
Timestamps : Disabled
InitialRto(ms) : 3000
ScalingHeuristics : Disabled
DynamicPortRangeStartPort : 49152
DynamicPortRangeNumberOfPorts : 16384
AutomaticUseCustom : Disabled
NonSackRttResiliency : Disabled
ForceWS : Disabled
MaxSynRetransmissions : 2
SettingName : DatacenterCustom
MinRto(ms) : 20
InitialCongestionWindow(MSS) : 4
CongestionProvider : DCTCP
CwndRestart : True
DelayedAckTimeout(ms) : 10
DelayedAckFrequency : 2
MemoryPressureProtection : Enabled
AutoTuningLevelLocal : Normal
AutoTuningLevelGroupPolicy : NotConfigured
AutoTuningLevelEffective : Local
EcnCapability : Enabled
Timestamps : Disabled
InitialRto(ms) : 3000
ScalingHeuristics : Disabled
DynamicPortRangeStartPort : 49152
DynamicPortRangeNumberOfPorts : 16384
AutomaticUseCustom : Disabled
NonSackRttResiliency : Disabled
ForceWS : Disabled
MaxSynRetransmissions : 2
SettingName : Compat
MinRto(ms) : 300
InitialCongestionWindow(MSS) : 2
CongestionProvider : Default
CwndRestart : False
DelayedAckTimeout(ms) : 200
DelayedAckFrequency : 2
MemoryPressureProtection : Enabled
AutoTuningLevelLocal : Normal
AutoTuningLevelGroupPolicy : NotConfigured
AutoTuningLevelEffective : Local
EcnCapability : Enabled
Timestamps : Disabled
InitialRto(ms) : 3000
ScalingHeuristics : Disabled
DynamicPortRangeStartPort : 49152
DynamicPortRangeNumberOfPorts : 16384
AutomaticUseCustom : Disabled
NonSackRttResiliency : Disabled
ForceWS : Disabled
MaxSynRetransmissions : 2
SettingName : Datacenter
MinRto(ms) : 20
InitialCongestionWindow(MSS) : 4
CongestionProvider : DCTCP
CwndRestart : True
DelayedAckTimeout(ms) : 10
DelayedAckFrequency : 2
MemoryPressureProtection : Enabled
AutoTuningLevelLocal : Normal
AutoTuningLevelGroupPolicy : NotConfigured
AutoTuningLevelEffective : Local
EcnCapability : Enabled
Timestamps : Disabled
InitialRto(ms) : 3000
ScalingHeuristics : Disabled
DynamicPortRangeStartPort : 49152
DynamicPortRangeNumberOfPorts : 16384
AutomaticUseCustom : Disabled
NonSackRttResiliency : Disabled
ForceWS : Disabled
MaxSynRetransmissions : 2
SettingName : Internet
MinRto(ms) : 300
InitialCongestionWindow(MSS) : 4
CongestionProvider : CTCP
CwndRestart : False
DelayedAckTimeout(ms) : 50
DelayedAckFrequency : 2
MemoryPressureProtection : Enabled
AutoTuningLevelLocal : Normal
AutoTuningLevelGroupPolicy : NotConfigured
AutoTuningLevelEffective : Local
EcnCapability : Enabled
Timestamps : Disabled
InitialRto(ms) : 3000
ScalingHeuristics : Disabled
DynamicPortRangeStartPort : 49152
DynamicPortRangeNumberOfPorts : 16384
AutomaticUseCustom : Disabled
NonSackRttResiliency : Disabled
ForceWS : Disabled
MaxSynRetransmissions : 2
You need to create the transport filter first, which specifies the TCP settings as a NetTcpSetting object, like in the example below.
New-NetTransportFilter -SettingName Custom -LocalPortStart 80 -LocalPortEnd 80 -RemotePortStart 0 -RemotePortEnd 65535
The Set-NetTCPSetting commandlet is used when you want to modify a setting. Hence why you're receiving the error regarding the custom object not found. After creating the transport filter, your original command to modify the settings should work.
Set-NetTCPSetting -SettingName Custom -InitialCongestionWindow 10 -CongestionProvider CTCP
Hi I get the same error when I run:
PS C:\Windows\system32> Get-NetTransportFilter
SettingName : Automatic
Protocol : TCP
LocalPortStart : 0
LocalPortEnd : 65535
RemotePortStart : 0
RemotePortEnd : 65535
DestinationPrefix : *
SettingName : DatacenterCustom
Protocol : TCP
LocalPortStart : 80
LocalPortEnd : 80
RemotePortStart : 0
RemotePortEnd : 65535
DestinationPrefix : *
In other words there is already a filter for port 80 (DataCenterCustom) and another for the others ports (Automatic) and for some reason I don't have the privileges to edit (I'm part of a domain network and I'm not in the main node).
What I do was change the name of the filter in the Set-NetTCPSetting run the second part:
Set-NetTCPSetting -SettingName DatacenterCustom -InitialCongestionWindow 10 -CongestionProvider CTCP
And that is the all, now is Works