Installation manual

99 ATTO Technology Inc. ATTO Utilities Installation and Operation Manual
3.5 Domain Validation Testing
Domain Validation tests the physical connection between storage controller and devices to ensure the desired
data transfer speeds can be achieved.
Domain Validation verifies the connection between the
storage controller and storage devices (i.e. cables,
connectors, targets, etc.) is capable of handling high-
speed data transfers.
The ATTO SCSIDV utility performs Domain Validation
on your storage connection. The three DV tests can be
selected in the
SCSIDV Main page .
Basic Integrity Test performs a simple integrity
check to determine the fastest valid mode of operation
between initiator and target, detecting most physical
configuration problems such as:
• path width errors
• expander errors
• gross cable errors
• incorrect termination
• damaged transceiver
Enhanced Integrity Test performs a more
advanced integrity check. A data pattern intended to
stress the physical domain is written to and then read
from memory on the device and compared with the
original data pattern. If data compare errors are
detected, fallback is attempted until a valid mode of
operation is found.
Problems detected include:
• cables with incorrect impedance
• bad SCSI device spacing
• poor termination
• marginal transceivers
• excessive crosstalk
• excessive system noise
Margining Test varies driver signal strength by +/-
20% and verifies the integrity of the subsystem.
Failure indicates the subsystem is close to failure
because inferior components are significantly
degrading SCSI bus signals and thus lowering the
signal margins. This can result in sudden subsystem
failure or intermittent integrity errors.
Running the SCSI Application
1 Launch the application.
2 Select the SCSI bus adapter channel.
3 Select the test(s) to be run.
4 Select the negotiation parameters located in
the Fallback Scheme grouping. The SDV test
starts with the highest values and, if a problem
is detected, tests with the next lower set of
values.
5 Select the target device(s). The test is
performed between the initiator and each target
device selected.
6 Press the Start button.
When the test is complete, a message panel displays.
The panel shows the negotiated SCSI parameters for
each device. The left side of the page shows the
negotiated value after the test runs and the right side
shows the value before the test being run.
The column labelled
Changed? indicates if the
negotiated value changed as a result of the tests. If the
value changed, the connection between the initiator
and the target device may not have been optimized.
The application
help text provides useful information
about setting up the tests. Review the
help text for
more detailed explanation of the application.