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Windows Server single-path and MPIO configuration recommendations for SC Series storage
32 Dell EMC SC Series Storage and Microsoft Multipath I/O | CML1004
Setting name
Description
Default
value
Recommended
value
MaxBurstLength
This is the negotiated Max Burst Length.
262144
(256KB)
no change
FirstBurstLength
This is the negotiated First Burst Length.
65536
(64KB)
no change
MaxRecvDataSegmentLength
This is the negotiated
MaxRecvDataSegmentLength.
65536
(64KB)
no change
IPSecConfigTimeout
This timeout value is used when the driver
calls the discovery service to
configure\release IPsec for an iSCSI
connection.
60
no change
InitialR2T
If set to Non-Zero value, initiator will
request InitialR2T (InitialR2T=Yes). Else
initiator will not request InitialR2T
(InitialR2T=No).
0
no change
ImmediateData
If set to Non-Zero value, initiator will
request ImmediateData
(ImmediateData=Yes). Else initiator will
not request ImmediateData
(ImmediateData=No).
1 (Yes)
no change
PortalRetryCount
This value is used to determine how many
times a connect request to a target portal
should be retried if the portal is down.
5
no change
NetworkReadyRetryCount
This value is used to determine how many
times initiator should retry getting the IP
address of NIC corresponding to the
PortNumber specified in the login request.
10
no change
ErrorRecoveryLevel
Error recovery level that the initiator will
request.
2
no change
Note the following additional guidelines:
Enable RFC1323 timestamps (TCP High Performance Extensions) to prevent sequence number wrap
under high load, known as Prevention Against Wrapped Sequence (PAWS). High-load iSCSI connections are
prone to this issue, particularly at 10GbE. Run this command at elevated CMD prompt to add a registry key
(set to value of 2 by default; this is the desired value):
netsh int tcp set global timestamps=enabled
HKLM\SYSTEM\CurrentControlSet\Services\TCPIP\Parameters\Tcp1323Opts
Values: 0 = Timestamps + windows scaling disabled.
1 = Windows Scaling Enabled
2 = Timestamps enabled ✓
3 = both enabled