How to disable autonegotiation ?

Hi Marga,

If you are running a recent version of Windows you can do this using PowerShell, or at least I can on a machine with X520 cards. At one point in Linux you'd use ethtool for this but I'm a bit old-fashioned in my use of Linux so there is possibly a better way in NetworkManager.

PS C:\Windows\system32> Get-NetAdapter | ? { $_.InterfaceDescription -match 'X520' } | Get-NetAdapterAdvancedProperty -RegistryKeyword '*SpeedDuplex' | ft -AutoSize Name,RegistryValue,ValidDisplayValues,ValidRegistryValues

Name RegistryValue ValidDisplayValues                                            ValidRegistryValues
---- ------------- ------------------                                            -------------------
VM2  {0}           {Auto Negotiation, 1.0 Gbps Full Duplex, 10 Gbps Full Duplex} {0, 6, 7}
VM1  {0}           {Auto Negotiation, 1.0 Gbps Full Duplex, 10 Gbps Full Duplex} {0, 6, 7}

PS C:\Windows\system32> Get-NetAdapter | ? { $_.InterfaceDescription -match 'X520' } | Set-NetAdapterAdvancedProperty -RegistryKeyword '*SpeedDuplex' -RegistryValue 6 | ft -AutoSize Name,RegistryValue,ValidDisplayValues,ValidRegistryValues

PS C:\Windows\system32> Get-NetAdapter | ? { $_.InterfaceDescription -match 'X520' } | Get-NetAdapterAdvancedProperty -RegistryKeyword '*SpeedDuplex' | ft -AutoSize Name,RegistryValue,ValidDisplayValues,ValidRegistryValues

Name RegistryValue ValidDisplayValues                                            ValidRegistryValues
---- ------------- ------------------                                            -------------------
VM2  {6}           {Auto Negotiation, 1.0 Gbps Full Duplex, 10 Gbps Full Duplex} {0, 6, 7}
VM1  {6}           {Auto Negotiation, 1.0 Gbps Full Duplex, 10 Gbps Full Duplex} {0, 6, 7}

Hope this helps

Kenny