README

ixgbe Linux* Base Driver for Intel(R) Ethernet Network Connections
******************************************************************

February 13, 2025


Contents
^^^^^^^^

* ixgbe Linux* Base Driver for Intel(R) Ethernet Network Connections

  * Overview

  * Related Documentation

  * Identifying Your Adapter

  * Important Notes

  * Building and Installation

  * Command Line Parameters

  * Additional Features and Configurations

  * Known Issues/Troubleshooting

  * Support

  * License

  * Trademarks


Overview
========

This driver supports Linux* kernel versions 2.6.x and newer. However,
some features may require a newer kernel version. The associated
Virtual Function (VF) driver for this driver is ixgbevf.

Driver information can be obtained using ethtool, lspci, and ip.
Instructions on updating ethtool can be found in the section
Additional Configurations later in this document.

This driver is only supported as a loadable module at this time. Intel
is not supplying patches against the kernel source to allow for static
linking of the drivers.

For questions related to hardware requirements, refer to the
documentation supplied with your Intel adapter. All hardware
requirements listed apply to use with Linux.

This driver supports XDP (Express Data Path) on kernel 4.14 and later
and AF_XDP zero-copy on kernel 4.18 and later. Note that XDP is
blocked for frame sizes larger than 3KB.

Note:

  Devices based on the Intel(R) Ethernet Connection X552 and Intel(R)
  Ethernet Connection X553 do not support the following features:

  * Energy Efficient Ethernet (EEE)

  * Intel PROSet for Windows Device Manager

  * Intel ANS teams or VLANs (LBFO is supported)

  * Fibre Channel over Ethernet (FCoE)

  * Data Center Bridging (DCB)

  * IPSec Offloading

  * MACSec Offloading

  In addition, SFP+ devices based on the Intel(R) Ethernet Connection
  X552 and Intel(R) Ethernet Connection X553 do not support the
  following features:

  * Speed and duplex auto-negotiation

  * Wake on LAN

  * 1000BASE-T SFP Modules


Related Documentation
=====================

See the "Intel(R) Ethernet Adapters and Devices User Guide" for
additional information on features. It is available on the Intel
website at https://cdrdv2.intel.com/v1/dl/getContent/705831.


Identifying Your Adapter
========================

The driver is compatible with devices based on the following:

* Intel(R) Ethernet Controller 82598

* Intel(R) Ethernet Controller 82599

* Intel(R) Ethernet Controller X520

* Intel(R) Ethernet Controller X540

* Intel(R) Ethernet Controller x550

* Intel(R) Ethernet Controller X552

* Intel(R) Ethernet Controller X553

* Intel(R) Ethernet Controller E610

For information on how to identify your adapter, and for the latest
Intel network drivers, refer to the Intel Support website at
https://www.intel.com/support.


SFP+ Devices with Pluggable Optics
----------------------------------


82599-Based Adapters
~~~~~~~~~~~~~~~~~~~~

Note:

  * If your 82599-based Intel(R) Network Adapter came with Intel
    optics or is an Intel(R) Ethernet Server Adapter X520-2, then it
    only supports Intel optics and/or the direct attach cables listed
    below.

  * When 82599-based SFP+ devices are connected back to back, they
    should be set to the same Speed setting via ethtool. Results may
    vary if you mix speed settings.

+-----------------------------------+-----------------------------------+-----------------------------------+
| Supplier                          | Type                              | Part Numbers                      |
|===================================|===================================|===================================|
| **SR Modules:**                   |                                   |                                   |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Intel                             | DUAL RATE 1G/10G SFP+ SR (bailed) | FTLX8571D3BCV-IT                  |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Intel                             | DUAL RATE 1G/10G SFP+ SR (bailed) | AFBR-703SDZ-IN2                   |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Intel                             | DUAL RATE 1G/10G SFP+ SR (bailed) | AFBR-703SDDZ-IN1                  |
+-----------------------------------+-----------------------------------+-----------------------------------+
| **LR Modules:**                   |                                   |                                   |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Intel                             | DUAL RATE 1G/10G SFP+ LR (bailed) | FTLX1471D3BCV-IT                  |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Intel                             | DUAL RATE 1G/10G SFP+ LR (bailed) | AFCT-701SDZ-IN2                   |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Intel                             | DUAL RATE 1G/10G SFP+ LR (bailed) | AFCT-701SDDZ-IN1                  |
+-----------------------------------+-----------------------------------+-----------------------------------+

The following is a list of third-party SFP+ modules that have received
some testing. Not all modules are applicable to all devices.

+-----------------------------------+-----------------------------------+-----------------------------------+
| Supplier                          | Type                              | Part Numbers                      |
|===================================|===================================|===================================|
| Finisar                           | SFP+ SR bailed, 10g single rate   | FTLX8571D3BCL                     |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Avago                             | SFP+ SR bailed, 10g single rate   | AFBR-700SDZ                       |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Finisar                           | SFP+ LR bailed, 10g single rate   | FTLX1471D3BCL                     |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Finisar                           | DUAL RATE 1G/10G SFP+ SR (No      | FTLX8571D3QCV-IT                  |
|                                   | Bail)                             |                                   |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Avago                             | DUAL RATE 1G/10G SFP+ SR (No      | AFBR-703SDZ-IN1                   |
|                                   | Bail)                             |                                   |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Finisar                           | DUAL RATE 1G/10G SFP+ LR (No      | FTLX1471D3QCV-IT                  |
|                                   | Bail)                             |                                   |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Avago                             | DUAL RATE 1G/10G SFP+ LR (No      | AFCT-701SDZ-IN1                   |
|                                   | Bail)                             |                                   |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Finisar                           | 1000BASE-T SFP                    | FCLF8522P2BTL                     |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Avago                             | 1000BASE-T                        | ABCU-5710RZ                       |
+-----------------------------------+-----------------------------------+-----------------------------------+
| HP                                | 1000BASE-SX SFP                   | 453153-001                        |
+-----------------------------------+-----------------------------------+-----------------------------------+

82599-based adapters support all passive and active limiting direct
attach cables that comply with SFF-8431 v4.1 and SFF-8472 v10.4
specifications.


Turning the laser off or on for SFP+
""""""""""""""""""""""""""""""""""""

Use the following to turn the laser off and on:

   ip link set [down|up] dev <ethX>


82599-Based QSFP+ Adapters
--------------------------

Note:

  * If your 82599-based Intel(R) Network Adapter came with Intel
    optics, it only supports Intel optics.

  * 82599-based QSFP+ adapters only support 4x10 Gbps connections.
    1x40 Gbps connections are not supported. QSFP+ link partners must
    be configured for 4x10 Gbps.

  * 82599-based QSFP+ adapters do not support automatic link speed
    detection. The link speed must be configured to either 10 Gbps or
    1 Gbps to match the link partners speed capabilities. Incorrect
    speed configurations will result in failure to link.

  * Intel(R) Ethernet Converged Network Adapter X520-Q1 only supports
    the optics and direct attach cables listed below.

+-----------------------------------+-----------------------------------+-----------------------------------+
| Supplier                          | Type                              | Part Numbers                      |
|===================================|===================================|===================================|
| Intel                             | DUAL RATE 1G/10G QSFP+ SRL        | E10GQSFPSR                        |
|                                   | (bailed)                          |                                   |
+-----------------------------------+-----------------------------------+-----------------------------------+

82599-based QSFP+ adapters support all passive and active limiting
QSFP+ direct attach cables that comply with SFF-8436 v4.1
specifications.


82598-Based Adapters
--------------------

Note:

  * Intel(R) Ethernet Network Adapters that support removable optical
    modules only support their original module type (for example, the
    Intel(R) 10 Gigabit SR Dual Port Express Module only supports SR
    optical modules). If you plug in a different type of module, the
    driver will not load.

  * Hot Swapping/hot plugging optical modules is not supported.

  * Only single speed, 10 gigabit modules are supported.

  * LAN on Motherboard (LOMs) may support DA, SR, or LR modules. Other
    module types are not supported. Please see your system
    documentation for details.

The following is a list of SFP+ modules and direct attach cables that
have received some testing. Not all modules are applicable to all
devices.

+-----------------------------------+-----------------------------------+-----------------------------------+
| Supplier                          | Type                              | Part Numbers                      |
|===================================|===================================|===================================|
| Finisar                           | SFP+ SR bailed, 10g single rate   | FTLX8571D3BCL                     |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Avago                             | SFP+ SR bailed, 10g single rate   | AFBR-700SDZ                       |
+-----------------------------------+-----------------------------------+-----------------------------------+
| Finisar                           | SFP+ LR bailed, 10g single rate   | FTLX1471D3BCL                     |
+-----------------------------------+-----------------------------------+-----------------------------------+

82598-based adapters support all passive direct attach cables that
comply with SFF-8431 v4.1 and SFF-8472 v10.4 specifications. Active
direct attach cables are not supported.

Third-party optic modules and cables referred to above are listed only
for the purpose of highlighting third party specifications and
potential compatibility, and are not recommendations or endorsements
or sponsorship of any third party's product by Intel. Intel is not
endorsing or promoting products made by any third party and the third
party reference is provided only to share information regarding
certain optic modules and cables with the above specifications. There
may be other manufacturers or suppliers, producing or supplying optic
modules and cables with similar or matching descriptions. Customers
must use their own discretion and diligence to purchase optic modules
and cables from any third party of their choice. Customers are solely
responsible for assessing the suitability of the product and/or
devices and for the selection of the vendor for purchasing any
product. THE OPTIC MODULES AND CABLES REFERRED TO ABOVE ARE NOT
WARRANTED OR SUPPORTED BY INTEL. INTEL ASSUMES NO LIABILITY
WHATSOEVER, AND INTEL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY,
RELATING TO SALE AND/OR USE OF SUCH THIRD PARTY PRODUCTS OR SELECTION
OF VENDOR BY CUSTOMERS.


Important Notes
===============


Do not unload port driver if VF with active VM is bound to it
-------------------------------------------------------------

Do not unload a port's driver if a Virtual Function (VF) with an
active Virtual Machine (VM) is bound to it. Doing so will cause the
port to appear to hang. Once the VM shuts down, or otherwise releases
the VF, the command will complete.


Configuring SR-IOV for improved network security
------------------------------------------------

In a virtualized environment, on Intel(R) Ethernet Network Adapters
that support SR-IOV, the virtual function (VF) may be subject to
malicious behavior. Software-generated layer two frames, like IEEE
802.3x (link flow control), IEEE 802.1Qbb (priority based flow-
control), and others of this type, are not expected and can throttle
traffic between the host and the virtual switch, reducing performance.
To resolve this issue, and to ensure isolation from unintended traffic
streams, configure all SR-IOV enabled ports for VLAN tagging from the
administrative interface on the PF. This configuration allows
unexpected, and potentially malicious, frames to be dropped.


Building and Installation
=========================


To manually build the driver
----------------------------

1. Move the base driver tar file to the directory of your choice. For
   example, use "/home/username/ixgbe" or "/usr/local/src/ixgbe".

2. Untar/unzip the archive, where "<x.x.x>" is the version number for
   the driver tar file:

      tar zxf ixgbe-<x.x.x>.tar.gz

3. Change to the driver src directory, where "<x.x.x>" is the version
   number for the driver tar:

      cd ixgbe-<x.x.x>/src/

4. Compile the driver module:

      make install

   The binary will be installed as:

      /lib/modules/<KERNEL VER>/updates/drivers/net/ethernet/intel/ixgbe/ixgbe.ko

   The install location listed above is the default location. This may
   differ for various Linux distributions.

5. Load the module using the modprobe command.

   To check the version of the driver and then load it:

      modinfo ixgbe
      modprobe ixgbe [parameter=port1_value,port2_value]

   Alternately, make sure that any older ixgbe drivers are removed
   from the kernel before loading the new module:

      rmmod ixgbe; modprobe ixgbe

6. Assign an IP address to the interface by entering the following,
   where "<ethX>" is the interface name that was shown in dmesg after
   modprobe:

      ip address add <IP_address>/<netmask bits> dev <ethX>

7. Verify that the interface works. Enter the following, where
   "IP_address" is the IP address for another machine on the same
   subnet as the interface that is being tested:

      ping <IP_address>

Note:

  For certain distributions like (but not limited to) Red Hat
  Enterprise Linux 7 and Ubuntu, once the driver is installed, you may
  need to update the initrd/initramfs file to prevent the OS loading
  old versions of the ixgbe driver.For Red Hat distributions:

     dracut --force

  For Ubuntu:

     update-initramfs -u


To build a binary RPM package of this driver
--------------------------------------------

Note:

  RPM functionality has only been tested in Red Hat distributions.

1. Run the following command, where "<x.x.x>" is the version number
   for the driver tar file:

      rpmbuild -tb ixgbe-<x.x.x>.tar.gz

   Note:

     For the build to work properly, the currently running kernel MUST
     match the version and configuration of the installed kernel
     sources. If you have just recompiled the kernel, reboot the
     system before building.

2. After building the RPM, the last few lines of the tool output
   contain the location of the RPM file that was built. Install the
   RPM with one of the following commands, where "<RPM>" is the
   location of the RPM file:

      rpm -Uvh <RPM>

   or:

      dnf/yum localinstall <RPM>

Note:

  * To compile the driver on some kernel/arch combinations, you may
    need to install a package with the development version of libelf
    (e.g. libelf-dev, libelf-devel, elfutils-libelf-devel).

  * When compiling an out-of-tree driver, details will vary by
    distribution. However, you will usually need a kernel-devel RPM or
    some RPM that provides the kernel headers at a minimum. The RPM
    kernel-devel will usually fill in the link at "/lib/modules/'uname
    -r'/build".


To build ixgbe driver with DCA
------------------------------

If your kernel supports Direct Cache Access (DCA), the driver will
build by default with DCA enabled.

Note:

  DCA is not supported on X550-based and E610-based adapters.


Command Line Parameters
=======================

If the driver is built as a module, enter optional parameters on the
command line with the following syntax:

   modprobe ixgbe [<option>=<VAL1>,<VAL2>,...]

There needs to be a "<VAL#>" for each network port in the system
supported by this driver. The values will be applied to each instance,
in function order. For example:

   modprobe ixgbe InterruptThrottleRate=16000,16000

In this case, there are two network ports supported by ixgbe in the
system.

* The default value for each parameter is generally the recommended
  setting, unless otherwise noted.


RSS
---

Valid Range: 0-16

* 0 = Assign up to the lesser value of the number of CPUs or the
  number of queues

* X = Assign X queues, where X is less than or equal to the maximum
  number of queues (16 queues).

RSS also affects the number of transmit queues allocated on 2.6.23 and
newer kernels with "CONFIG_NETDEVICES_MULTIQUEUE" set in the kernel
".config" file. "CONFIG_NETDEVICES_MULTIQUEUE" only exists from 2.6.23
to 2.6.26. Other options enable multiqueue in 2.6.27 and newer
kernels.


Multiqueue
----------

Valid Range: 0, 1

* 0 = Disables Multiple Queue support

* 1 = Enabled Multiple Queue support (a prerequisite for RSS)


Direct Cache Access (DCA)
-------------------------

Valid Range: 0, 1

* 0 = Disables DCA support in the driver

* 1 = Enables DCA support in the driver

If the driver is enabled for DCA, this parameter allows load-time
control of the feature.

Note:

  DCA is not supported on X550-based and E610-based adapters.


IntMode
-------

Valid Range: 0-2

* 0 = Legacy Int

* 1 = MSI

* 2 = MSI-X

IntMode controls the allowed load time control over the type of
interrupt registered for by the driver. MSI-X is required for multiple
queue support, and some kernels and combinations of kernel ".config"
options will force a lower level of interrupt support. "cat
/proc/interrupts" will show different values for each type of
interrupt.


InterruptThrottleRate
---------------------

Valid Range:

* 0=off

* 1=dynamic

* "<min_ITR>-<max_ITR>"

Interrupt Throttle Rate controls the number of interrupts each
interrupt vector can generate per second. Increasing ITR lowers
latency at the cost of increased CPU utilization, though it may help
throughput in some circumstances.

* 0 = Setting "InterruptThrottleRate" to 0 turns off any interrupt
  moderation and may improve small packet latency. However, this is
  generally not suitable for bulk throughput traffic due to the
  increased CPU utilization of the higher interrupt rate.

  Note:

    * On 82599, and X540, X550-based and E610-based adapters,
      disabling "InterruptThrottleRate" will also result in the driver
      disabling HW RSC.

    * On 82598-based adapters, disabling "InterruptThrottleRate" will
      also result in disabling LRO (Large Receive Offloads).

* 1 = Setting "InterruptThrottleRate" to Dynamic mode attempts to
  moderate interrupts per vector while maintaining very low latency.
  This can sometimes cause extra CPU utilization. If planning on
  deploying ixgbe in a latency sensitive environment, this parameter
  should be considered.

* "<min_ITR>-<max_ITR>" = 956-488281

  Setting "InterruptThrottleRate" to a value greater or equal to
  "<min_ITR>" will program the adapter to send at most that many
  interrupts per second, even if more packets have come in. This
  reduces interrupt load on the system and can lower CPU utilization
  under heavy load, but will increase latency as packets are not
  processed as quickly.


LLI (Low Latency Interrupts)
----------------------------

Low Latency Interrupts (LLI) allow for immediate generation of an
interrupt upon processing receive packets that match certain criteria
as set by the parameters described below. LLI parameters are not
enabled when Legacy interrupts are used. You must be using MSI or
MSI-X (see "cat /proc/interrupts") to successfully use LLI.

Note:

  LLI is not supported on X550-based and E610-based adapters.


LLIPort
-------

Valid Range: 0-65535

LLI is configured with the "LLIPort" command line parameter, which
specifies which TCP port should generate Low Latency Interrupts.

For example, using "LLIPort=80" would cause the board to generate an
immediate interrupt upon receipt of any packet sent to TCP port 80 on
the local machine.

Warning:

  Enabling LLI can result in an excessive number of interrupts/second
  that may cause problems with the system and in some cases may cause
  a kernel panic.

Note:

  LLI is not supported on X550-based and E610-based adapters.


LLIPush
-------

Valid Range: 0-1

"LLIPush" can be set to be enabled or disabled (default). It is most
effective in an environment with many small transactions.

Note:

  * Enabling LLIPush may allow a denial of service attack.

  * LLI is not supported on X550-based and E610-based adapters.


LLISize
-------

Valid Range: 0-1500

"LLISize" causes an immediate interrupt if the board receives a packet
smaller than the specified size.

Note:

  LLI is not supported on X550-based and E610-based adapters.


LLIEType
--------

Valid Range: 0-0x8FFF

This parameter specifies the Low Latency Interrupt (LLI) Ethernet
protocol type.

Note:

  LLI is not supported on X550-based and E610-based adapters.


LLIVLANP
--------

Valid Range: 0-7

This parameter specifies the LLI on VLAN priority threshold.

Note:

  LLI is not supported on X550-based and E610-based adapters.


FdirPballoc
-----------

Valid Range: 1-3

Specifies the Intel(R) Ethernet Flow Director allocated packet buffer
size.

* 1 = 64k

* 2 = 128k

* 3 = 256k


AtrSampleRate
-------------

Valid Range: 0-255

This parameter is used with the Intel Ethernet Flow Director and is
the software ATR transmit packet sample rate. For example, when
"AtrSampleRate" is set to 20, every 20th packet looks to see if the
packet will create a new flow. A value of 0 indicates that ATR should
be disabled and no samples will be taken.


max_vfs
-------

Valid Range:  1-63

This parameter adds support for SR-IOV. It causes the driver to spawn
up to "max_vfs" worth of virtual functions.

If the value is greater than 0 it will also force the "VMDq" parameter
to be 1 or more.

Note:

  This parameter is only used on kernel 3.7.x and below. On kernel
  3.8.x and above, use sysfs to enable VFs. Use sysfs for Red Hat
  distributions.

For example, you can create 4 VFs as follows:

   echo 4 > /sys/class/net/<ethX>/device/sriov_numvfs

To disable VFs, write 0 to the same file:

   echo 0 > /sys/class/net/<ethX>/device/sriov_numvfs

The parameters for the driver are referenced by position. Thus, if you
have a dual port adapter, or more than one adapter in your system, and
want N virtual functions per port, you must specify a number for each
port with each parameter separated by a comma. For example, the
following will spawn 4 VFs on the first port:

   modprobe ixgbe max_vfs=4

The following will spawn 2 VFs on the first port and 4 VFs on the
second port:

   modprobe ixgbe max_vfs=2,4

Note:

  * Use caution when loading the driver with these parameters.
    Depending on your system configuration, number of slots, etc., it
    is impossible to predict in all cases where the positions would be
    on the command line.

  * Neither the device nor the driver control how VFs are mapped into
    config space. Bus layout will vary by operating system. On
    operating systems that support it, you can check sysfs to find the
    mapping.

  * When either SR-IOV mode or VMDq mode is enabled, hardware VLAN
    filtering and VLAN tag stripping/insertion will remain enabled.
    Please remove the old VLAN filter before the new VLAN filter is
    added. For example:

       ip link set eth0 vf 0 vlan 100    // set vlan 100 for VF 0
       ip link set eth0 vf 0 vlan 0      // Delete vlan 100
       ip link set eth0 vf 0 vlan 200    // set a new vlan 200 for VF 0

With kernel 3.6, the driver supports the simultaneous usage of
"max_vfs" and DCB features, subject to the constraints described
below. Prior to kernel 3.6, the driver did not support the
simultaneous operation of "max_vfs" greater than 0 and the DCB
features (multiple traffic classes utilizing Priority Flow Control and
Extended Transmission Selection).

When DCB is enabled, network traffic is transmitted and received
through multiple traffic classes (packet buffers in the NIC). The
traffic is associated with a specific class based on priority, which
has a value of 0 through 7 used in the VLAN tag. When SR-IOV is not
enabled, each traffic class is associated with a set of
receive/transmit descriptor queue pairs. The number of queue pairs for
a given traffic class depends on the hardware configuration. When SR-
IOV is enabled, the descriptor queue pairs are grouped into pools. The
Physical Function (PF) and each Virtual Function (VF) is allocated a
pool of receive/transmit descriptor queue pairs. When multiple traffic
classes are configured (for example, DCB is enabled), each pool
contains a queue pair from each traffic class. When a single traffic
class is configured in the hardware, the pools contain multiple queue
pairs from the single traffic class.

The number of VFs that can be allocated depends on the number of
traffic classes that can be enabled. The configurable number of
traffic classes for each enabled VF is as follows:

* 0 - 15 VFs = Up to 8 traffic classes, depending on device support

* 16 - 31 VFs = Up to 4 traffic classes

* 32 - 63 VFs = 1 traffic class

When VFs are configured, the PF is allocated one pool as well. The PF
supports the DCB features with the constraint that each traffic class
will only use a single queue pair. When zero VFs are configured, the
PF can support multiple queue pairs per traffic class.


LRO
---

Valid Range: 0 (off), 1 (on)

Large Receive Offload (LRO) is a technique for increasing inbound
throughput of high-bandwidth network connections by reducing CPU
overhead. It works by aggregating multiple incoming packets from a
single stream into a larger buffer before they are passed higher up
the networking stack, thus reducing the number of packets that have to
be processed. LRO combines multiple Ethernet frames into a single
receive in the stack, thereby potentially decreasing CPU utilization
for receives.

This technique is also referred to as Hardware Receive Side Coalescing
(HW RSC). 82599, X540, X550-based and E610-based adapters support HW
RSC. The LRO parameter controls HW RSC enablement.

You can verify that the driver is using LRO by looking at these
counters in ethtool:

hw_rsc_aggregated:
   Counts total packets that were combined

hw_rsc_flushed:
   Counts the number of packets flushed out of LRO

Note:

  IPv6 and UDP are not supported by LRO.


EEE (Energy Efficient Ethernet)
-------------------------------

Valid Range: 0-1

* 0 = Disables EEE

* 1 = Enables EEE

A link between two EEE-compliant devices will result in periodic
bursts of data followed by periods where the link is in an idle state.
This Low Power Idle (LPI) state is supported at 1Gbps and 10Gbps link
speeds.

Note:

  * EEE support requires auto-negotiation.

  * Both link partners must support EEE.

  * EEE is not supported on all Intel(R) Ethernet Network devices or
    at all link speeds.

Example:

   ethtool --show-eee <ethX>
   ethtool --set-eee <ethX> [eee on|off]


DMAC
----

Valid Range: 0, 41-10000

This parameter enables or disables DMA Coalescing (DMAC) feature.
Values are in microseconds and set the internal DMA Coalescing
internal timer.

DMAC is available on Intel(R) X550 (and later) and E610-based based
adapters.

DMA (Direct Memory Access) allows the network device to move packet
data directly to the system's memory, reducing CPU utilization.
However, the frequency and random intervals at which packets arrive do
not allow the system to enter a lower power state. DMA Coalescing
allows the adapter to collect packets before it initiates a DMA event.
This may increase network latency but also increases the chances that
the system will enter a lower power state. Turning on DMA Coalescing
may save energy with kernel 2.6.32 and newer. DMA Coalescing must be
enabled across all active ports in order to save platform power.

InterruptThrottleRate (ITR) should be set to dynamic. When "ITR=0",
DMA Coalescing is automatically disabled.


MDD (Malicious Driver Detection)
--------------------------------

Valid Range: 0-1

* 0 = Disabled

* 1 = Enabled

This parameter is only relevant for devices operating in SR-IOV mode.
When this parameter is set, the driver detects malicious VF driver and
disables its Tx/Rx queues until a VF driver reset occurs.


Additional Features and Configurations
======================================


ethtool
-------

The driver utilizes the ethtool interface for driver configuration and
diagnostics, as well as displaying statistical information. The latest
ethtool version is required for this functionality. Download it at
https://kernel.org/pub/software/network/ethtool/.


Configuring the Driver on Different Distributions
-------------------------------------------------

Configuring a network driver to load properly when the system is
started is distribution dependent. Typically, the configuration
process involves adding an alias line to "/etc/modules.conf" or
"/etc/modprobe.conf" as well as editing other system startup scripts
and/or configuration files. Many popular Linux distributions ship with
tools to make these changes for you. To learn the proper way to
configure a network device for your system, refer to your distribution
documentation. If during this process you are asked for the driver or
module name, the name for the Base Driver is ixgbe.

For example, if you install the ixgbe driver for two adapters (eth0
and eth1) and want to set the interrupt mode to MSI-X and MSI,
respectively, add the following to "modules.conf" or
"/etc/modprobe.conf":

   alias eth0 ixgbe
   alias eth1 ixgbe
   options ixgbe IntMode=2,1


Viewing Link Messages
---------------------

Link messages will not be displayed to the console if the distribution
is restricting system messages. In order to see network driver link
messages on your console, set dmesg to eight by entering the
following:

   dmesg -n 8

Note:

  This setting is not saved across reboots.


Jumbo Frames
------------

Jumbo Frames support is enabled by changing the Maximum Transmission
Unit (MTU) to a value larger than the default value of 1500.

Use the ip command to increase the MTU size. For example, enter the
following where "<ethX>" is the interface number:

   ip link set mtu 9000 dev <ethX>
   ip link set up dev <ethX>

This setting is not saved across reboots.

Add "MTU=9000" to the following file to make the setting change
permanent:

* For RHEL: "/etc/sysconfig/network-scripts/ifcfg-<ethX>"

* For SLES: "/etc/sysconfig/network/<config_file>"

Note:

  * The maximum MTU setting for jumbo frames is 9710. This corresponds
    to the maximum jumbo frame size of 9728 bytes.

  * This driver will attempt to use multiple page sized buffers to
    receive each jumbo packet. This should help to avoid buffer
    starvation issues when allocating receive packets.

  * Packet loss may have a greater impact on throughput when you use
    jumbo frames. If you observe a drop in performance after enabling
    jumbo frames, enabling flow control may mitigate the issue.

  * For 82599-based network connections, if you are enabling jumbo
    frames in a virtual function (VF), jumbo frames must first be
    enabled in the physical function (PF). The VF MTU setting cannot
    be larger than the PF MTU.


Speed and Duplex Configuration
------------------------------

In addressing speed and duplex configuration issues, you need to
distinguish between copper-based adapters and fiber-based adapters.

In the default mode, an Intel(R) Ethernet Network Adapter using copper
connections will attempt to auto-negotiate with its link partner to
determine the best setting. If the adapter cannot establish link with
the link partner using auto-negotiation, you may need to manually
configure the adapter and link partner to identical settings to
establish link and pass packets. This should only be needed when
attempting to link with an older switch that does not support auto-
negotiation or one that has been forced to a specific speed or duplex
mode. Your link partner must match the setting you choose. 1Gbps
speeds and higher cannot be forced. Use the autonegotiation
advertising setting to manually set devices for 1Gbps and higher.

Speed, duplex, and autonegotiation advertising are configured through
the ethtool utility.

To see the speed configurations your device supports, run the
following:

   ethtool <ethX>

By default, devices based on the Intel(R) Ethernet Controller x550 do
not advertise 2.5Gbps or 5Gbps. To have your device advertise these
speeds, use the following:

   ethtool -s <ethX> advertise N

Where "N" is a combination of the following:

100baseTFull:
   0x008

1000baseTFull:
   0x020

2500baseTFull:
   0x800000000000

5000baseTFull:
   0x1000000000000

10000baseTFull:
   0x1000

For example, to turn on all modes:

   ethtool -s <ethX> advertise 0x1800000001028

For more details, refer to the ethtool man page.

Note:

  On Linux systems with "INTERFACES(5)", this can be specified as a
  "pre-up" command in "/etc/network/interfaces" so that the interface
  is always brought up with NBASE-T support. For example:

     iface <ethX> inet dhcp
       pre-up ethtool -s <ethX> advertise 0x1800000001028 || true

Important:

  Only experienced network administrators should force speed and
  duplex or change autonegotiation advertising manually. The settings
  at the switch must always match the adapter settings. Adapter
  performance may suffer or your adapter may not operate if you
  configure the adapter differently from your switch.

An Intel(R) Ethernet Network Adapter using fiber-based connections,
however, will not attempt to auto-negotiate with its link partner
since those adapters operate only in full duplex and only at their
native speed.

Note:

  For the Intel(R) Ethernet Connection X552 10 GbE SFP+, you must
  specify the desired speed.


Link-Level Flow Control (LFC)
-----------------------------

Ethernet Flow Control (IEEE 802.3x) can be configured with ethtool to
enable receiving and transmitting pause frames for ixgbe. When
transmit is enabled, pause frames are generated when the receive
packet buffer crosses a predefined threshold. When receive is enabled,
the transmit unit will halt for the time delay specified when a pause
frame is received.

Note:

  You must have a flow control capable link partner.

Flow Control is enabled by default.

Use ethtool to change the flow control settings.

To enable or disable Rx or Tx Flow Control:

   ethtool -A <ethX> rx <on|off> tx <on|off>

Note:

  This command only enables or disables Flow Control if auto-
  negotiation is disabled. If auto-negotiation is enabled, this
  command changes the parameters used for auto-negotiation with the
  link partner.

To enable or disable auto-negotiation:

   ethtool -s <ethX> autoneg <on|off>

Note:

  * Flow Control auto-negotiation is part of link auto-negotiation.
    Depending on your device, you may not be able to change the auto-
    negotiation setting.

  * The ixgbe driver requires flow control on both the port and link
    partner. If flow control is disabled on one of the sides, the port
    may appear to hang on heavy traffic.

  * For 82598 backplane cards entering 1 gigabit mode, flow control
    default behavior is changed to off. Flow control in 1 gigabit mode
    on these devices can lead to transmit hangs.


Intel(R) Ethernet Flow Director
-------------------------------

The Intel(R) Ethernet Flow Director (Intel(R) Ethernet FD) performs
the following tasks:

* Directs receive packets according to their flows to different queues

* Enables tight control on routing a flow in the platform

* Matches flows and CPU cores for flow affinity

* Supports multiple parameters for flexible flow classification and
  load balancing (in SFP mode only)

Note:

  An included script ("set_irq_affinity") automates setting the IRQ to
  CPU affinity.

This driver supports the following flow types:

* IPv4

* TCPv4

* UDPv4

* SCTPv4

* TCPv6

* UDPv6

Each flow type supports valid combinations of IP addresses (source or
destination) and UDP/TCP ports (source and destination). You can
supply only a source IP address, a source IP address and a destination
port, or any combination of one or more of these four parameters.

Note:

  This driver does not support IPv6 source or destination IP
  addresses.

See the Intel(R) Ethernet Adapters and Devices User Guide for a table
that summarizes supported Intel Ethernet Flow Director features across
Intel(R) Ethernet controllers.


Sideband Perfect Filters
------------------------

Sideband Perfect Filters are used to direct traffic that matches
specified characteristics. They are enabled through ethtool's ntuple
interface. To enable or disable the Intel Ethernet Flow Director and
these filters:

   ethtool -K <ethX> ntuple <off|on>

Note:

  When you disable ntuple filters, all the user programmed filters are
  flushed from the driver cache and hardware. All needed filters must
  be re-added when ntuple is re-enabled.

To display all of the active filters:

   ethtool -u <ethX>

To add a new filter:

   ethtool -U <ethX> flow-type <type> src-ip <ip> [m <ip_mask>] dst-ip <ip>
   [m <ip_mask>] src-port <port> [m <port_mask>] dst-port <port> [m <port_mask>]
   action <queue>

Where:

<ethX>:
   The Ethernet device to program.

<type>:
   Can be ip4, tcp4, udp4, sctp4, ip6, tcp6, udp6, sctp6.

<ip>:
   The IP address to match on.

<ip_mask>:
   The IPv4 address to mask on.

   Note:

     These filters use inverted masks.

<port>:
   The port number to match on.

<port_mask>:
   The 16-bit integer for masking.

   Note:

     These filters use inverted masks.

<queue>:
   The queue to direct traffic toward ("-1" discards the matched
   traffic).

To delete a filter:

   ethtool -U <ethX> delete <N>

Where "<N>" is the filter ID displayed when printing all the active
filters, and may also have been specified using "loc <N>" when adding
the filter.

Note:

  Intel Ethernet Flow Director masking works in the opposite manner
  from subnet masking. For instance, in the following command:

     ethtool -U eth11 flow-type ip4 src-ip 172.4.1.2 m 255.0.0.0 dst-ip \
     172.21.1.1 m 255.128.0.0 action 31

  The "src-ip" value that is written to the filter will be 0.4.1.2,
  not 172.0.0.0 as might be expected. Similarly, the "dst-ip" value
  written to the filter will be 0.21.1.1, not 172.0.0.0.

EXAMPLES:

To add a filter that directs packet to queue 2:

   ethtool -U <ethX> flow-type tcp4 src-ip 192.168.10.1 dst-ip \
   192.168.10.2 src-port 2000 dst-port 2001 action 2 [loc 1]

To set a filter using only the source and destination IP address:

   ethtool -U <ethX> flow-type tcp4 src-ip 192.168.10.1 dst-ip \
   192.168.10.2 action 2 [loc 1]

To match TCP traffic sent from 192.168.0.1, port 5300, directed to
192.168.0.5, port 80, and then send it to queue 7:

   ethtool -U enp130s0 flow-type tcp4 src-ip 192.168.0.1 dst-ip 192.168.0.5
   src-port 5300 dst-port 80 action 7

To add a TCPv4 filter with a partial mask for a source IP:

   ethtool -U <ethX> flow-type tcp4 src-ip 192.168.0.0 m 0.255.255.255 dst-ip
   192.168.5.12 src-port 12600 dst-port 31 action 12

Note:

  For each flow-type, the programmed filters must all have the same
  matching input set. For example, issuing the following two commands
  is acceptable:

     ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.1 src-port 5300 action 7
     ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.5 src-port 55 action 10

  Issuing the next two commands, however, is not acceptable, since the
  first specifies "src-ip" and the second specifies "dst-ip":

     ethtool -U enp130s0 flow-type ip4 src-ip 192.168.0.1 src-port 5300 action 7
     ethtool -U enp130s0 flow-type ip4 dst-ip 192.168.0.5 src-port 55 action 10

  The second command will fail with an error. You may program multiple
  filters with the same fields, using different values, but, on one
  device, you may not program two tcp4 filters with different matching
  fields.The ixgbe driver does not support matching on a subportion of
  a field, thus partial mask fields are not supported.


Filters to Direct Traffic to a Specific VF
------------------------------------------

It is possible to create filters that direct traffic to a specific
Virtual Function. For older versions of ethtool, this depends on the
"action" parameter. Specify the action as a 64-bit value, where the
lower 32 bits represent the queue number, while the next 8 bits
represent the VF ID. Note that 0 is the PF, so the VF identifier is
offset by 1. For example:

   ethtool -U <ethX> flow-type tcp4 src-ip 192.168.10.1 dst-ip \
   192.168.10.2 src-port 2000 dst-port 2001 action 0x800000002 [loc 1]

The "action" field specifies to direct traffic to Virtual Function 7
(8 minus 1) into queue 2 of that VF.

Newer versions of ethtool (version 4.11 and later) use "vf" and
"queue" parameters instead of the "action" parameter. Note that using
the new ethtool "vf" parameter does not require the value to be offset
by 1. This command is equivalent to the above example:

   ethtool -U <ethX> flow-type tcp4 src-ip 192.168.10.1 dst-ip \
   192.168.10.2 src-port 2000 dst-port 2001 vf 7 queue 2 [loc 1]

Note that these filters will not break internal routing rules, and
will not route traffic that otherwise would not have been sent to the
specified VF.


Flex Byte Intel Ethernet Flow Director Filters
----------------------------------------------

The driver also supports matching user-defined data within the packet
payload. This flexible data is specified using the "user-def" field of
the ethtool command in the following way:

   +----------------------------+--------------------------+
   | 31    28    24    20    16 | 15    12    8    4    0  |
   +----------------------------+--------------------------+
   | offset into packet payload | 2 bytes of flexible data |
   +----------------------------+--------------------------+

For example:

   ... user-def 0x4FFFF ...

tells the filter to look 4 bytes into the payload and match that value
against 0xFFFF. The offset is based on the beginning of the payload,
and not the beginning of the packet. Thus:

   flow-type tcp4 ... user-def 0x8BEAF ...

would match TCP/IPv4 packets which have the value 0xBEAF 8 bytes into
the TCP/IPv4 payload.

Note that ICMP headers are parsed as 4 bytes of header and 4 bytes of
payload. Thus to match the first byte of the payload, you must
actually add 4 bytes to the offset. Also note that ip4 filters match
both ICMP frames as well as raw (unknown) ip4 frames, where the
payload will be the L3 payload of the IP4 frame.

The maximum offset is 64. The hardware will only read up to 64 bytes
of data from the payload. The offset must be even because the flexible
data is 2 bytes long and must be aligned to byte 0 of the packet
payload.

The user-defined flexible offset is also considered part of the input
set and cannot be programmed separately for multiple filters of the
same type. However, the flexible data is not part of the input set and
multiple filters may use the same offset but match against different
data.


Support for UDP RSS
-------------------

This feature adds an ON/OFF switch for hashing over certain flow
types. Only UDP can be turned on. The default setting is disabled.

Only support for enabling/disabling hashing on ports for UDP over IPv4
(UDP4) or IPv6 (UDP6) is supported.

Note:

  Fragmented packets may arrive out of order when RSS UDP support is
  configured.

Supported Ethtool Commands and Options:

-n, --show-nfc

Retrieves the receive network flow classification configurations.

-n rx-flow-hash tcp4|udp4|ah4|esp4|sctp4|tcp6|udp6|ah6|esp6|sctp6
   Retrieves the hash options for the specified network traffic type.

-N, --config-nfc

Configures the receive network flow classification.

-N rx-flow-hash
tcp4|udp4|ah4|esp4|sctp4|tcp6|udp6|ah6|esp6|sctp6|m|v|t|s|d|f|n|r...
   Configures the hash options for the specified network traffic type.

   udp4:
      UDP over IPv4

   udp6:
      UDP over IPv6

   f:
      Hash on bytes 0 and 1 of the Layer 4 header of the Rx packet.

   n:
      Hash on bytes 2 and 3 of the Layer 4 header of the Rx packet.

The following is an example using udp4 (UDP over IPv4):

* To include UDP port numbers in RSS hashing:

     ethtool -N <ethX> rx-flow-hash udp4 sdfn

* To exclude UDP port numbers from RSS hashing:

     ethtool -N <ethX> rx-flow-hash udp4 sd

* To display UDP hashing current configuration:

     ethtool -n <ethX> rx-flow-hash udp4

The results of running that call will be the following, if UDP hashing
is enabled:

   UDP over IPV4 flows use these fields for computing Hash flow key:
     IP SA
     IP DA
     L4 bytes 0 & 1 [TCP/UDP src port]
     L4 bytes 2 & 3 [TCP/UDP dst port]

The results if UDP hashing is disabled are shown below:

   UDP over IPV4 flows use these fields for computing Hash flow key:
     IP SA
     IP DA

Note:

  Parameters "FdirPballoc" and "AtrSampleRate" impact Intel Ethernet
  Flow Director.


Data Center Bridging (DCB)
--------------------------

Note:

  The kernel assumes that TC0 is available, and will disable Priority
  Flow Control (PFC) on the device if TC0 is not available. To fix
  this, ensure TC0 is enabled when setting up DCB on your switch.

DCB is a configuration Quality of Service implementation in hardware.
It uses the VLAN priority tag (802.1p) to filter traffic. That means
that there are 8 different priorities that traffic can be filtered
into. It also enables priority flow control (802.1Qbb) which can limit
or eliminate the number of dropped packets during network stress.
Bandwidth can be allocated to each of these priorities, which is
enforced at the hardware level (802.1Qaz).

DCB is normally configured on the network using the DCBX protocol
(802.1Qaz), a specialization of LLDP (802.1AB). The ixgbe driver
supports the following variants of DCBX support:

* Software-based DCBX mode only

Note:

  Intel Ethernet 500 Series adapters do not support firmware DCBX.

In software-based mode, LLDP traffic is forwarded to the network stack
and user space, where a software agent can handle it. In this mode,
the adapter can operate in either "willing" or "nonwilling" DCBX mode
and DCB configuration can be both queried and set locally.

Note:

  In software-based DCBX mode, you can configure DCB parameters using
  software LLDP/DCBX agents that interface with the Linux kernel's DCB
  Netlink API. We recommend using OpenLLDP as the DCBX agent when
  running in software mode. For more information, see the OpenLLDP man
  pages and https://github.com/intel/openlldp.


Configuring VLAN Tagging on SR-IOV Enabled Adapter Ports
--------------------------------------------------------

To configure VLAN tagging for the ports on an SR-IOV enabled adapter,
use the following command. The VLAN configuration should be done
before the VF driver is loaded or the VM is booted. The VF is not
aware of the VLAN tag being inserted on transmit and removed on
received frames (sometimes called "port VLAN" mode).

   ip link set dev <ethX> vf <id> vlan <vlan id>

For example, the following will configure PF eth0 and the first VF on
VLAN 10:

   ip link set dev eth0 vf 0 vlan 10


Controlling the VF link state
-----------------------------

The ixgbe PF driver allows a root user to disable the VF link state
using iproute2.

To control the VF link state, use the following:

   ip link set <ethX> vf <number> state auto|disable

Where:

auto:
   Automatically reflects the link state from the PF to the VF
   (default).

disable:
   Tells the hardware to drop any packets sent by the VF.

Note:

  The ixgbe driver does not support the "enable" option. If the
  command does not work, it may not be supported by your system.


Virtual Function (VF) Tx Rate Limit
-----------------------------------

Use the ip command to configure the Tx rate limit for a VF from the PF
interface.

For example, to set a Tx rate limit of 1000Mbps for VF 0:

   ip link set eth0 vf 0 rate 1000

Note that the limit is set per queue and not for the entire VF
interface.


Malicious Driver Detection (MDD) for VFs
----------------------------------------

Some Intel Ethernet devices use Malicious Driver Detection (MDD) to
detect malicious traffic from the VF and disable Tx/Rx queues or drop
the offending packet until a VF driver reset occurs. You can view MDD
messages in the PF's system log using the dmesg command.

* If the PF driver logs MDD events from the VF, confirm that the
  correct VF driver is installed.

* To restore functionality, you can manually reload the VF or VM.

On devices based on the Intel Ethernet Controller X520, the ixgbe
driver will detect certain types of misbehavior from the VF and
automatically disable the VF by default. To change this behavior, use
the following command:

   ethtool --set-priv-flags <ethX> mdd-disable-vf on|off

Where:

on:
   Disables the VF if the PF detects VF misbehavior.

off:
   Resets but does not disable the VF if the PF detects VF
   misbehavior.


MAC and VLAN Anti-Spoofing Feature for VFs
------------------------------------------

When a malicious driver on a Virtual Function (VF) interface attempts
to send a spoofed packet, it is dropped by the hardware and not
transmitted.

An interrupt is sent to the PF driver notifying it of the spoof
attempt. When a spoofed packet is detected, the PF driver will send
the following message to the system log (displayed by the "dmesg"
command), where "X" is the PF interface number and "n" is number of
spoofed packets:

   ixgbe <ethX>: ixgbe_spoof_check: n spoofed packets detected

Note:

  This feature can be disabled for a specific VF:

     ip link set <ethX> vf <vf id> spoofchk {off|on}


Setting MAC Address, VLAN, and Rate Limit Using IProute2 Tool
-------------------------------------------------------------

You can set a MAC address of a Virtual Function (VF), a default VLAN,
and the rate limit using the IProute2 tool. Download the latest
version of the IProute2 tool from Sourceforge if your version does not
have all the features you require.


Wake on LAN (WoL) Support
-------------------------

Some adapters do not support Wake on LAN (WoL). To determine if your
adapter supports WoL, run the following command:

   ethtool <ethX>

WoL is configured through the ethtool utility. If your Linux
distribution does not include ethtool, download and install it from
the following website:
https://kernel.org/pub/software/network/ethtool/.

For instructions on enabling WoL with ethtool, refer to the website
listed above.

WoL will be enabled on the system during the next shutdown or reboot.
For this driver version, in order to enable WoL, the ixgbe driver must
be loaded prior to shutting down or suspending the system.

Note:

  The Intel(R) Ethernet Converged Network Adapter X550-T1 and Intel(R)
  Ethernet Converged Network Adapter X550-T2 have a manageability/AUX
  power connector. These devices only support WoL if AUX power is
  supplied via this connector. Note that this is system and adapter
  specific. Some with this connector do not support WoL. Some systems
  do not provide the correct power connection. See your system
  documentation for details.


Firmware Logs
-------------

Intel Ethernet E610 Series devices support Firmware Logs. The ixgbe
driver allows you to generate firmware logs for supported categories
of events, to help debug issues with Customer Support.

* The driver supports firmware logging via the debugfs interface on PF
  0 only.

* Firmware logs are stored in a data file in binary form.

The following operations are supported.

Activate Firmware Logs:

   echo 1 > /sys/kernel/debug/ixgbe/0000:18:00.0/fwlog/enable

Save data to a file:

   cat /sys/kernel/debug/ixgbe/0000:18:00.0/fwlog/data > fwlog.bin

The Firmware Logs can be configured by writing to the 'fwlog/modules'
file like this:

   echo <fwlog_event> <fwlog_level> > /sys/kernel/debug/ixgbe/0000:18:00.0/fwlog/modules

* "<fwlog_event>" represents the following supported events:

  * "CTRL" - Control

  * "LINK" - Link Management

  * "LINK_TOPO" - Link Topology Detection

  * "I2C" - I2C

  * "SDP" - SDP

  * "MDIO" - MDIO

  * "ADMINQ" - Admin Queue

  * "NVM" - NVM

  * "AUTH" - Authentication

  * "VPD" - Vital Product Data

  * "IOSF" - Intel On-Chip System Fabric

  * "WATCHDOG" - Watchdog

  * "TASK_DISPATCH" - Task Dispatcher

  * "MNG" - Manageability

  * "HEALTH" - Health

  * "TSDRV" - Time Sync

  * "PFREG" - PF Registration

  * "MDLVER" - Module Version

  * "ALL" - Allows to set all of the modules to the specified
    "fwlog_level" or to read the "fwlog_level" of all of the modules

* "<fwlog_level>" is the desired verbosity level of the firmware logs.
  Supported values include:

  * NONE

  * ERROR

  * WARNING

  * NORMAL

  * VERBOSE

Example usage to configure the modules:

   echo LINK VERBOSE > /sys/kernel/debug/ixgbe/0000:18:00.0/fwlog/modules

The Firmware Logs resolution can be adjusted using following command:

   echo 50 > /sys/kernel/debug/ixgbe/0000:18:00.0/fwlog/resolution

Example value 50 means that Firmware will send at least 50 messages
per single event. Available values are within 1..128 range.

The Firmware Logs buffers can be configured by following command:

   echo 128 > /sys/kernel/debug/ixgbe/0000:18:00.0/fwlog/nr_buffs

Memory for allocation of 128 ring buffers is requested here. The
available values are within 1..512 range. In X86 architecture, ring
buffers are 4 kb in size for Firmware Logs. So, Ring buffers shall
have at least 4kb size for other CPU architectures too.


Debug Dump
----------

Intel Ethernet E610 Series devices support debug dump, which allows
you to obtain runtime register values from the firmware for "clusters"
of events and then write the results to a single dump file, for
debugging complicated issues in the field.

This debug dump contains a snapshot of the device and its existing
hardware configuration, such as switch tables, transmit scheduler
tables, and other information. Debug dump captures the current state
of the specified cluster(s) and is a stateless snapshot of the whole
device.

Note:

  * Like with firmware logs, the contents of the debug dump are not
    human-readable. You must work with Customer Support to decode the
    file.

  * Debug dump is per device, not per PF.

The ixgbe driver uses the debugfs interface for debug dump. To
generate a debug dump file in Linux, do the following:

1. Specify the cluster(s) to include in the dump file, using one of
   the following commands. You can either set a single cluster or all
   clusters.

   * To dump all clusters:

        echo > /sys/kernel/debug/ixgbe/<pci_addr>/fw/dump_cluster_id

   * To dump a single cluster:

        echo <cluster ID> > /sys/kernel/debug/ixgbe/<pci_addr>/fw/dump_cluster_id

     Possible values for "<cluster ID>" are:

        * 0 - Link

        * 1 - CSR

   For example, to dump the CSR space, use the following:

      echo 1 > /sys/kernel/debug/ixgbe/<pci_addr>/fw/dump_cluster_id

2. Save the debug dump to a file, using one of the following. Replace
   the ".bin" name with the file name you want to use. For example:

   * For the file dumped using one of the previous commands:

        cat /sys/kernel/debug/ixgbe/<pci_addr>/fw/debug_dump > ~/single_cluster_dump.bin


IEEE 1588 Precision Time Protocol (PTP) Hardware Clock (PHC)
------------------------------------------------------------

Precision Time Protocol (PTP) is used to synchronize clocks in a
computer network. PTP support varies among Intel devices that support
this driver. Use the following command to get a definitive list of PTP
capabilities supported by the device:

   ethtool -T <ethX>


Tunnel/Overlay Stateless Offloads
---------------------------------

Supported tunnels and overlays include VXLAN, GENEVE, and others
depending on hardware and software configuration. Stateless offloads
are enabled by default.

To view the current state of all offloads:

   ethtool -k <ethX>


Interrupt Rate Limiting
-----------------------

This driver supports an adaptive interrupt throttle rate (ITR)
mechanism that is tuned for general workloads. Use ethtool to
customize the interrupt rate control for specific workloads, adjusting
the number of microseconds between interrupts:

   ethtool -C <ethX> rx-usecs N

Values for "N" can be:

0:
   No limit

1:
   Adaptive (default).

2-1022:
   Minimum microseconds between each interrupt.

The range of 0-1022 microseconds provides an effective range of 978 to
500,000 interrupts per second. The underlying hardware supports
granularity in 2us intervals at 1Gbps and 10Gbps and 20us at 100Mbps,
so adjacent values may result in the same interrupt rate.

For lower CPU utilization:

* Lower Rx and Tx interrupts per queue using ethtool.

* Setting "rx-usecs" to 125 will limit interrupts to about 8,000
  interrupts per second per queue:

     ethtool -C <ethX> rx-usecs 125

For reduced latency:

* Disable ITR by setting "rx-usecs" to 0 using ethtool:

     ethtool -C <ethX> rx-usecs 0


Using Devlink to update a device's NVM
--------------------------------------

When you update the NVM on some devices, the update may use the
devlink interface, rather than the ethtool interface. This will happen
if the following are true:

* You are updating an Intel Ethernet E610 Series device.

* Your system is running a distro that supports the "devlink dev
  flash" command.

* The firmware currently installed on the device supports it.

* The new NVM conforms to the correct PLDM format.

On devices that support it, you can also use the devlink command line
directly to update the device NVM. However, for a feature rich,
usability experience we recommend that you use NVMUpdate.

   devlink dev flash pci/0000:63:00.0 file filename.bin

Where:

pci/0000:63:00.0:
   The device you wish to update. You can get a list of devices with
   the "devlink dev info" command.

filename.bin:
   The file that contains the new NVM image.


Known Issues/Troubleshooting
============================


Software Issues
---------------

If your Intel Ethernet Network Connection is not working after
installing the driver, verify that you have installed the correct
driver.

Intel(R) Active Management Technology 2.0, 2.1, and 2.5 are not
supported in conjunction with the Linux driver.


Receive Error counts may be higher than the actual packet error count
---------------------------------------------------------------------

When a packet is received with more than one error, two bad packets
may be reported. This affects all devices based on 10G, or faster,
controllers.


MAC address of Virtual Function changes unexpectedly
----------------------------------------------------

If a Virtual Function's MAC address is not assigned in the host, then
the VF (virtual function) driver will use a random MAC address. This
random MAC address may change each time the VF driver is reloaded. You
can assign a static MAC address in the host machine. This static MAC
address will survive a VF driver reload.


SR-IOV virtual functions have identical MAC addresses
-----------------------------------------------------

When you create multiple SR-IOV virtual functions, the VFs may have
identical MAC addresses. Only one VF will pass traffic, and all
traffic on other VFs with identical MAC addresses will fail. This is
related to the "MACAddressPolicy=persistent" setting in
"/usr/lib/systemd/network/99-default.link".

To resolve this issue, edit the
"/usr/lib/systemd/network/99-default.link" file and change the
"MACAddressPolicy" line to "MACAddressPolicy=none". For more
information, see the systemd.link man page.


Multiple Interfaces on Same Ethernet Broadcast Network
------------------------------------------------------

Due to the default ARP behavior on Linux, it is not possible to have
one system on two IP networks in the same Ethernet broadcast domain
(non-partitioned switch) behave as expected. All Ethernet interfaces
will respond to IP traffic for any IP address assigned to the system.
This results in unbalanced receive traffic.

If you have multiple interfaces in a server, turn on ARP filtering by
entering the following:

   echo 1 > /proc/sys/net/ipv4/conf/all/arp_filter

This only works if your kernel's version is higher than 2.4.5.

Note:

  This setting is not saved across reboots. The configuration change
  can be made permanent by adding the following line to the file
  "/etc/sysctl.conf":

     net.ipv4.conf.all.arp_filter = 1

Another alternative is to install the interfaces in separate broadcast
domains (either in different switches or in a switch partitioned to
VLANs).


UDP Stress Test Dropped Packet Issue
------------------------------------

Under small packet UDP stress with the ixgbe driver, the system may
drop UDP packets due to socket buffers being full. Setting the driver
Intel Ethernet Flow Control variables to the minimum may resolve the
issue. You may also try increasing the kernel's default buffer sizes
by changing the values in:

   /proc/sys/net/core/rmem_default and rmem_max


Cisco Catalyst 4948-10GE port resets may cause switch to shut down ports
------------------------------------------------------------------------

82598-based hardware can re-establish link quickly and when connected
to some switches, rapid resets within the driver may cause the switch
port to become isolated due to "link flap." This is typically
indicated by a yellow instead of a green link light. Several
operations may cause this problem, such as repeatedly running ethtool
commands that cause a reset.

A potential workaround is to use the Cisco IOS command "no errdisable
detect cause all" from the Global Configuration prompt, which enables
the switch to keep the interfaces up, regardless of errors.


Rx Page Allocation Errors
-------------------------

"Page allocation failure. order:0" errors may occur under stress with
kernels 2.6.25 and newer. This is caused by the way the Linux kernel
reports this stressed condition.


DCB: GSO causes bandwidth allocation issues
-------------------------------------------

In order for DCB to work correctly, Generic Segmentation Offload
(GSO), also known as software TSO, must be disabled using ethtool.
Since the hardware supports TSO (hardware offload of segmentation),
GSO will not be running by default. Use the following to query the GSO
state:

   ethtool -k <ethX>

When using 82598-based network connections, ixgbe driver only supports
16 queues on a platform with more than 16 cores.

Due to known hardware limitations, RSS can only filter in a maximum of
16 receive queues.

82599, X540, X550-based network connections support up to 64 queues.


Lower than expected performance
-------------------------------

Some PCIe x8 slots are actually configured as x4 slots. These slots
have insufficient bandwidth for full line rate with dual port and quad
port devices. In addition, if you put a PCIe v4.0 or v3.0-capable
adapter into a PCIe v2.x slot, you cannot get full bandwidth. The
driver detects this situation and writes one of the following messages
in the system log:

   PCI-Express bandwidth available for this card is not sufficient for optimal
   performance. For optimal performance a x8 PCI-Express slot is required.

or:

   PCI-Express bandwidth available for this device may be insufficient for
   optimal performance. Please move the device to a different PCI-e link with
   more lanes and/or higher transfer rate."

If this error occurs, moving your adapter to a true PCIe v3.0 x8 slot
will resolve the issue.


Running "ethtool -t <ethX>" command causes break between PF and test client
---------------------------------------------------------------------------

When there are active VFs, "ethtool -t" will only run the link test.
The driver will also log in syslog that VFs should be shut down to run
a full diagnostic test.


Unable to obtain DHCP lease on boot with Red Hat
------------------------------------------------

In configurations where the auto-negotiation process takes more than 5
seconds, the boot script may fail with the following message:

   <ethX>: failed. No link present. Check cable?

This error may occur even though the presence of link can be confirmed
using "ethtool <ethX>". In this case, try setting "LINKDELAY=30" in
"/etc/sysconfig/network-scripts/ifdfg-<ethX>".

The same issue can occur during a network boot (via PXE) on Red Hat
distributions that use the dracut script:

   Warning: No carrier detected on interface <ethX>

In this case, add "rd.net.timeout.carrier=30" at the kernel command
line.

Note:

  Link time can vary. Adjust the "LINKDELAY" value accordingly.


Host may reboot after removing PF when VF is active in guest
------------------------------------------------------------

Using kernel versions earlier than 3.2, do not unload the PF driver
with active VFs. Doing this will cause your VFs to stop working until
you reload the PF driver and may cause a spontaneous reboot of your
system.

Prior to unloading the PF driver, you must first ensure that all VFs
are no longer active. Do this by shutting down all VMs and unloading
the VF driver.


Out of memory issues on IA32 systems
------------------------------------

The driver may consume a lot of memory based on the number of CPUs and
network interfaces. This leads to memory segmentation. Thus, the
driver may not be able to allocate enough memory. To resolve this,
reduce the number of descriptors using ethtool -G or the number of
queues through the RSS parameter.


VLAN tags are stripped on kernels earlier than 2.6.36
-----------------------------------------------------

In order to support DCB, kernels earlier than 2.6.36 strip VLAN tags
for VLAN0. This ensures connectivity using 802.1p frames between
kernels that have built-in support and kernels that do not.

If the VLAN tags are necessary AND DCB is NOT used, disable VLAN
stripping on older kernels at build time with the following:

   make CFLAGS_EXTRA=-DIXGBE_DISABLE_8021P_SUPPORT


Support
=======

For general information, go to the Intel support website at
https://www.intel.com/support/

or the Intel Ethernet Linux project hosted by GitHub at
https://github.com/intel/ethernet-linux-ixgbe

If an issue is identified with the released source code on a supported
kernel with a supported adapter, contact Intel Customer Support at
https://www.intel.com/content/www/us/en/support/products/36773
/ethernet-products.html


License
=======

This program is free software; you can redistribute it and/or modify
it under the terms and conditions of the GNU General Public License,
version 2, as published by the Free Software Foundation.

This program is distributed in the hope it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301
USA.

The full GNU General Public License is included in this distribution
in the file called "COPYING".

Copyright (c) 1999 - 2024, Intel Corporation.


Trademarks
==========

Intel is a trademark or registered trademark of Intel Corporation or
its subsidiaries in the United States and/or other countries.

Other names and brands may be claimed as the property of others.