How to enable auto-negotiation of ConnectX-3(MT27500 Family)

My ethernet device is ConnectX-3(MT27500 Family), which has 10GBASE-KR F/W.

The device is connected to another 10GBASE-KR device(Not ethernet switch), which is the auto-negotiation is ‘on’. The connection is not linked because my device is the auto-negotiation is ‘off’.

I would like to know how I can enable the auto-negotiation.

The following is ethtool log of my device.

[root@localhost ~]# ethtool enp4s0

Settings for enp4s0:

Supported ports: [ Backplane ]

Supported link modes: 10000baseKR/Full

Supported pause frame use: Symmetric Receive-only

Supports auto-negotiation: Yes

Advertised link modes: 10000baseKR/Full

Advertised pause frame use: Symmetric

Advertised auto-negotiation: Yes

Speed: Unknown!

Duplex: Unknown! (255)

Port: None


Transceiver: internal

Auto-negotiation: off

Supports Wake-on: d

Wake-on: d

Current message level: 0x00000014 (20)

link ifdown

Link detected: no


To enable autonegotiation via ethtool:

ethtool -s enp4s0 autoneg on

That said, there are a few considerations to check:

  1. If the ConnectX-3 is set to auto-negotiate in a back-to-back connection with another HCA, one of the devices in the link will need to be set to a forced speed in order for the link to be established. Where the above command would enable autonegiation, a back-to-back peer would need:

ethtool -s enp4s0 speed 10000 duplex full

  1. Check the ConnectX-3 firmware release notes’ for the version you are using and verify that the cable/transceiver connecting the ConnectX-3 and peer device as well as the peer device itself are listed in the compatibility matrices. For more information, select your model of ConnectX-3 from the link below, select the firmware version you are using, and the page will provide a link to the Firmware Release notes:

  1. If the cable and peer device are validated within the firmware’s Release Notes and you are still unable to establish a link, please open a case with our support team as we will require more information in order to assist with the issue. If you do not have a valid support contract, please contact to discuss a contract.

Thank you,

Nvidia Network Support