6.0.1

Table Of Contents
Configuring Advanced Parameters for iSCSI
You might need to congure additional parameters for your iSCSI initiators. For example, some iSCSI
storage systems require ARP (Address Resolution Protocol) redirection to move iSCSI trac dynamically
from one port to another. In this case, you must activate ARP redirection on your host.
The following table lists advanced iSCSI parameters that you can congure using the vSphere Web Client. In
addition, you can use the vSphere CLI commands to congure some of the advanced parameters. For
information, see the Geing Started with vSphere Command-Line Interfaces documentation.
I Do not make any changes to the advanced iSCSI seings unless you are directed by VMware
support or Storage Vendors.
Table 105. Additional Parameters for iSCSI Initiators
Advanced Parameter Description Configurable On
Header Digest Increases data integrity. When header digest is enabled, the system
performs a checksum over each iSCSI Protocol Data Unit’s (PDU’s)
header part and veries using the CRC32C algorithm.
Software iSCSI
Dependent Hardware
iSCSI
Data Digest Increases data integrity. When data digest is enabled, the system
performs a checksum over each PDU's data part and veries using
the CRC32C algorithm.
N Systems that use Intel Nehalem processors ooad the iSCSI
digest calculations for software iSCSI, thus reducing the impact on
performance.
Software iSCSI
Dependent Hardware
iSCSI
Maximum
Outstanding R2T
Denes the R2T (Ready to Transfer) PDUs that can be in transition
before an acknowledge PDU is received.
Software iSCSI
Dependent Hardware
iSCSI
First Burst Length Species the maximum amount of unsolicited data an iSCSI
initiator can send to the target during the execution of a single SCSI
command, in bytes.
Software iSCSI
Dependent Hardware
iSCSI
Maximum Burst
Length
Maximum SCSI data payload in a Data-In or a solicited Data-Out
iSCSI sequence, in bytes.
Software iSCSI
Dependent Hardware
iSCSI
Maximum Receive
Data Segment Length
Maximum data segment length, in bytes, that can be received in an
iSCSI PDU.
Software iSCSI
Dependent Hardware
iSCSI
Session Recovery
Timeout
Species the amount of time, in seconds, that can lapse while a
session recovery is performed. If the timeout exceeds its limit, the
iSCSI initiator terminates the session.
Software iSCSI
Dependent Hardware
iSCSI
No-Op Interval Species the time interval, in seconds, between NOP-Out requests
sent from your iSCSI initiator to an iSCSI target. The NOP-Out
requests serve as the ping mechanism to verify that a connection
between the iSCSI initiator and the iSCSI target is active.
Software iSCSI
Dependent Hardware
iSCSI
No-Op Timeout Species the amount of time, in seconds, that can lapse before your
host receives a NOP-In message. The message is sent by the iSCSI
target in response to the NOP-Out request. When the no-op timeout
limit is exceeded, the initiator terminates the current session and
starts a new one.
Software iSCSI
Dependent Hardware
iSCSI
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