System-level Configuration
NetXtreme-E User’s Manual
February 26, 2018 • NetXtreme-E-UG100
Page 43
Operational Link Speed
This option configures the link speed used by the preboot (MBA and UEFI) drivers (Linux, ESX), OS driver, and
firmware. This setting is overridden by the driver setting in the OS present state. The Windows driver
(bnxtnd_.sys) uses linkspeed settings in the driver .inf file.
Firmware Link Speed
This option configures the link speed used by the firmware when the device is in D3.
Auto-negotiation Protocol
This is the supported auto-negotiation protocol used to negotiate the link speed with the link partner. This option
must match the AN protocol setting in the link partner port. The Broadcom NetXtreme-E NIC supports the
following auto-negotiation protocols: IEEE 802.3by, 25G/50G consortiums and 25G/50G BAM. By default, this
option is set to IEEE 802.3by and falls back to 25G/50G consortiums.
Link speed and Flow Control/Pause must be configured in the driver in the host OS.
Windows Driver Settings
To access the Windows driver settings:
Open
Windows Device Manager -> Broadcom NetXtreme E Series adapter -> Advanced Properties ->
Advanced tab
Flow Control = Auto-Negotiation
This enables Flow Control/Pause frame AN.
Speed and Duplex = Auto-Negotiation
This enables link speed AN.
Linux Driver Settings
ethtool -s eth0 speed 25000 autoneg off
This command turns off auto-negotiation and forces the link speed to 25 Gbps.
ethtool -s eth0 autoneg on advertise 0x0
This command enables auto-negotiation and advertises that the device supports all speeds: 1G, 10G, 25G.
Note:
For 10GBase-T NetXtreme-E network adapters, auto-negotiation must be enabled.
The 25G advertisement is a newer standard first defined in the 4.7 kernel's ethtool interface. To fully
support these new advertisement speeds for auto-negotiation, a 4.7 (or newer) kernel and a newer
ethtool utility (version 4.8) are required.
