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Windows Server single-path and MPIO configuration recommendations for SC Series storage
53 Dell EMC SC Series: Microsoft Multipath I/O Best Practices | CML1004
Recommended registry settings location:
HKLM\SYSTEM\CurrentControlSet\Services\mpio\Parameters
Setting name
Description
Default
value
Recommended
value
PDORemovePeriod
This setting controls the number of
seconds that the multipath pseudo-LUN
remains in system memory, even after
losing all paths to the device. When this
timer value is exceeded, pending I/O
operations will be failed, and the failure is
exposed to the application rather than
attempting to continue to recover active
paths. The maximum time allowed is
MAXULONG (49,000 seconds).
20
120
PathRecoveryInterval
This represents the period after which
PathRecovery is attempted. This setting is
only used if it is not set to 0 and
UseCustomPathRecoveryInterval is set to
1.
40
25
UseCustomPathRecoveryInterval
If this key exists and is set to 1, it allows
the use of PathRecoveryInterval.
0
1
PathVerifyEnabled
This flag enables path verification by MPIO
on all paths every N seconds (where N
depends on the value set in
PathVerificationPeriod).
This Boolean function must be filled with
either 0 (disable) or 1 (enable). By default,
it is disabled.
0
1
PathVerificationPeriod
This setting is used to indicate the number
of seconds with which MPIO has been
requested to perform path verification. This
field is only honored if PathVerifyEnabled
is TRUE. This timer is specified in
seconds. The default is 30 seconds. The
maximum allowed is MAXULONG.
30
no change
RetryCount
This setting specifies the number of times
a failed I/O if the DSM determines that a
failing request must be retried. This is
invoked when DsmInterpretError() returns
Retry = TRUE. The default setting is 3.
3
no change
(FC or iSCSI
systems)
15 (front-end
SAS systems
only)