In Windows Server 2008 or Windows Server 2008 R2 environment, if the network environment is set to enable Delay ACK and storage is connected with iSCSI, an iScsiPrt error is output to the System Event Log when a general operation is executed

Disable Delay ACK

Setting the Registry value TcpAckFrequency to 1
according to the technical information below will disable Delay ACK. This will
prevent the resend processing time from going to 5 frame/sec when a packet is
dropped. Using this method will not prevent packets from being dropped, but
even if they are dropped the resend processing delay will be improved, so that
time outs will not occur.


Entry: TcpAckFrequency
Value Type: REG_DWORD, number
Range: 0-255
Default: 2


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