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Cisco Bug: CSCuj31489 - Twinax Generates CRC Errors at Int Intel X520-DA2

Last Modified

Feb 20, 2018

Products (1)

  • Cisco Unified Computing System

Known Affected Releases


Description (partial)

Adapter firmware matches that of a working server, and we're not seeing any CRC errors upstream at the switch.  We only see self-generated Receive CRC Errors at the adapter.  This is seen with both V02 and V03 5M Twinax in the customer's environment.

SFP-H10GB-CU5M - 37-0962-03 / PN: COPQAA5JAB - Version 3
SFP-H10GB-CU5M - 37-0962-02 / PN: COPQAA5JAA - Version 2

Intel X520-DA2
1.5(1l) firmware
SFP-H10GB-CU5M - 37-0962-03 / PN: COPQAA5JAB - Version 3

Because of the high number of CRC errors at the adapter, we experienced a 50% loss in I/O, and sometimes we experienced ping loss and link negotiation issues.

Sample Output from Host:
~ # esxcli network nic stats get -n vmnic3
NIC statistics for vmnic3
   Packets received: 13883283
   Packets sent: 12358044
   Bytes received: 19269442683
   Bytes sent: 16884457486
   Receive packets dropped: 0
   Transmit packets dropped: 0
   Total receive errors: 4174  < ---- Receive Errors
   Receive length errors: 2
   Receive over errors: 0
   Receive CRC errors: 4172 < --- Receive CRC Errors
   Receive frame errors: 0
   Receive FIFO errors: 0
   Receive missed errors: 0
   Total transmit errors: 0
   Transmit aborted errors: 0
   Transmit carrier errors: 0
   Transmit FIFO errors: 0
   Transmit heartbeat errors: 0
   Transmit window errors: 0
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