R/Evolution 2000 Series, Troubleshooting Manual

Page: 49 / 130

Chapter 4 Troubleshooting Using RAIDar 49
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CRC Error Count – In a sequence of SAS transfers (frames), the data is
protected by a cyclic redundancy check (CRC) value. This error count
specifies the number of times the computed CRC does not match the CRC
stored in the frame, which indicates that the frame might have been corrupted
in transit.
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Inter-Connect Error Count – Specifies the number of times the lane between
two expanders experienced a communication error.
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Lost Doubleword Count – Specifies the number of times the PHY has lost
doubleword synchronization and restarted the Link Reset sequence.
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Invalid Doubleword Count – Specifies the number of invalid doublewords that
have been received by the PHY, not including those received during Link
Reset sequences.
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Reset Error Count – Specifies the number of times the expander performed a
reset.
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Phy Disabled – Specifies whether the PHY is enabled (True) or disabled
(False).
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Fault Reason – A coded value that explains why the EC isolated the PHY. If
the PHY is active, this value is 0x0.
For example, assume that a SAS cable connects Enclosure 0’s “out” port to
Enclosure 1’s “in” port. If the connection has no faults then PHYs associated with
each port have OK status, as shown in the following figure.
However, if there is a fault in the SAS cable or either of the SAS connectors then
associated PHYs have Non-Critical status as shown in the following figure.
Enclosure 0 Enclosure 1
Enclosure 0 Enclosure 1