General Related Troubleshooting

Linux Kernel Upstream Release Notes v6.5

Issue

Cause

Solution

Link down

The link might be down due to one of the following issues:

  • cable issues,

  • unsupported speeds,

  • configuration issues

Run mlx5cmd -dbg -pddrinfo and check the following lines in the output presented:

  • Troubleshooting Info:

    • Messages: Indicates the issue that requires attention.

  • Operational Info:

    • Active link speed: The active speed displayed in bit mask. The list of bits are stated below.

    • Supported speeds: The supported speed displayed in bit mask. The list of bits are stated below.

Ethernet:

  • 100GB: Bits 23-20

  • 56GB: Bit 8

  • 50GB: Bits 31-30; 19-18

  • 40GB: Bits 16-15; 7

  • 25GB: Bits 29-28

  • 20GB: Bit 5

  • 10GB: Bits 14-12; 4-2

  • 1G: Bit 1

InfiniBand:

  • Bit 0: SDR

  • Bit 1: DDR

  • Bit 2: QDR

  • Bit 4: FDR

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