FreeBSD* Driver for Intel^® Ethernet

NOTE: This release includes two 10 gigabit FreeBSD Base Drivers for Intel® Ethernet. These drivers are named em and igb.

• The igb driver supports all 82575 and 82576-based gigabit network connections.

• The em driver supports all other gigabit network connections.

First identify your adapter.  Then follow the appropriate steps for building, installing, and configuring the appropriate driver.

Identifying Your Adapter

For information on how to identify your adapter, go to the Adapter & Driver ID Guide at:

http://support.intel.com/support/go/network/adapter/idguide.htm

For the latest Intel network drivers for FreeBSD, see:

http://support.intel.com/support/go/network/adapter/home.htm

NOTE: The Intel® 82562v 10/100 Network Connection only supports 10/100 connectivity.

Using the EM Base Driver

Overview

Building and Installation

Speed and Duplex Configuration

Additional Configurations

Known Limitations

Support

Overview

This file describes the FreeBSD* driver for Intel^® Ethernet. This driver has been developed for use with all community-supported versions of FreeBSD.

For questions related to hardware requirements, refer to the documentation supplied with your Gigabit adapter. All hardware requirements listed apply for use with FreeBSD.

Building and Installation

NOTE: This driver package is to be used only as a standalone archive and the user should not attempt to incorporate it into the kernel source tree.

In the instructions below, x.x.x is the driver version as indicated in the name of the driver tar file.

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

2. Untar/unzip the archive:

   tar xzvf em-x.x.x.tar.gz

   This will create an em-x.x.x directory.

3. To create a loadable module, perform the following steps.

   1. To compile the module
        cd em-x.x.x
        make

   2. To install the compiled module to the system directory:
        make install

   3. If you want the driver to load automatically when the system is booted:
          1. Edit /boot/loader.conf, and add the following line.

      if_em_load="YES"

4. To assign an IP address to the interface, enter the following:
     ifconfig_em<interface_num> <IP_address>
    

5. 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>
    

6. To configure the IP address to remain after reboot, edit /etc/rc.conf, and create the appropriate ifconfig_em<interface_num> entry:
     ifconfig_em<interface_num>="<ifconfig_settings>"

   Example usage:
     ifconfig_em0="inet 102.168.10.1 netmask 255.255.255.0"
    

   NOTE: For assistance, see the ifconfig man page.

Speed and Duplex Configuration

By default, the adapter auto-negotiates the speed and duplex of the connection. If there is a specific need, the ifconfig utility can be used to configure the speed and duplex settings on the adapter. Example usage:

ifconfig emX <IP_address> media 100baseTX mediaopt full-duplex

NOTE: Only use mediaopt to set the driver to full-duplex. If mediaopt is not specified and you are not running at gigabit speed, the driver defaults to half-duplex.

If the interface is currently forced to 100 full duplex, in order to change to half duplex you must use this command:

    ifconfig emX <IP_address> media 100baseTX -mediaopt full-duplex
 

This driver supports the following media type options:

For more information on the ifconfig utility, see the ifconfig man page.

Additional Configurations

The driver supports Transmit/Receive Checksum Offload and Jumbo Frames on all but the 82542-based adapters. For specific adapters, refer to the Identifying Your Adapter section.

Jumbo Frames

To enable Jumbo Frames, use the ifconfig utility to increase the Maximum Transmission Unit (MTU). The Jumbo Frames MTU range for Intel Adapters is 1500 to 16110 bytes, with a default value of 1500.

To modify MTU, enter the following:
        ifconfig emX <hostname or IP address> mtu 9000

To confirm the MTU used between two specific devices, use:
        route get <destination_IP_address>

NOTES: Only enable Jumbo Frames if your network infrastructure, including switches, supports them. The Jumbo Frames setting on the switch must be set to at least 22 bytes larger than that of the MTU.  Some Intel gigabit adapters that support Jumbo Frames have a frame size limit of 9238 bytes, with a corresponding MTU size limit of 9216 bytes. The adapters with this limitation are based on the Intel® 82571EB, 82572EI, 82573L, 82566, 82562, and 80003ES2LAN controllers. These correspond to the following product names: Intel®PRO/1000 PT Server Adapter Intel® PRO/1000 PT Desktop Adapter Intel® PRO/1000 PT Network Connection Intel® PRO/1000 PT Dual Port Server Adapter Intel® PRO/1000 PT Dual Port Network Connection Intel® PRO/1000 PT Quad Port Server Adapter Intel® PRO/1000 PF Quad Port Server Adapter Intel® PRO/1000 PF Server Adapter Intel® PRO/1000 PF Network Connection Intel® PRO/1000 PF Dual Port Server Adapter Intel® PRO/1000 PB Server Connection Intel®PRO/1000 PL Network Connection Intel® PRO/1000 EB Network Connection with I/O Acceleration Intel®PRO/1000 EB Backplane Connection with I/O Acceleration Intel® 82566DM-2 Gigabit Network Connection Intel® 82574L Gigabit Network Connection Intel® Gigabit CT Desktop Adapter Intel® 82567LM-4 Gigabit Network Connection Intel® 82567LM-3 Gigabit Network Connection Intel® 82567LF-3 Gigabit Network Connection Using Jumbo frames at 10 or 100 Mbps is not supported and may result in poor performance or loss of link. The following adapters do not support Jumbo Frames: Intel®PRO/1000 Gigabit Server Adapter Intel® PRO/1000 PM Network Connection Intel® 82562V 10/100 Network Connection Intel® 82566DM Gigabit Network Connection Intel® 82566DC Gigabit Network Connection Intel® 82566MM Gigabit Network Connection Intel® 82566MC Gigabit Network Connection Intel® 82562GT 10/100 Network Connection Intel® 82562G 10/100 Network Connection Intel® 82566DC-2 Gigabit Network Connection Intel® 82562V-2 10/100 Network Connection Intel® 82562G-2 10/100 Network Connection Intel® 82562GT-2 10/100 Network Connection Intel® 82567V-3 Gigabit Network Connection

VLANs

To create a new VLAN interface:

ifconfig <vlan_name> create

To associate the VLAN interface with a physical interface and assign an IP address, netmask, and VLAN ID:

ifconfig <vlan_name> <ip_address> netmask <subnet_mask> vlan <vlan_id> vlandev <physical_interface>

Example:

ifconfig vlan10 10.0.0.1 netmask 255.255.255.0 vlan 10 vlandev em0

In this example, all packets will be marked on egress with 802.1Q VLAN tags, specifying a VLAN ID of 10.

To remove a VLAN interface:

ifconfig <vlan_name> destroy

Polling

	NOTES: Device Polling is only valid for non-SMP kernels.
	The driver has to be built into the kernel for Device Polling to be enabled in the driver.

To enable polling in the driver, add the following options to the kernel configuration, and then recompile the kernel:

options DEVICE_POLLING
options HZ=1000

At runtime:
        use sysctl kern.polling.enable=1 to turn polling on

        use sysctl kern.polling.enable=0 to turn polling off

Checksum Offload

• Checksum offloading is not supported on 82542 Gigabit adapters.

• Checksum offloading supports both TCP and UDP packets and is supported for both transmit and receive.

• Checksum offloading can be enabled or disabled using ifconfig. Both transmit and receive offloading will be either enabled or disabled together. You cannot enable/disable one without the other.

To enable checksum offloading:

ifconfig emX rxcsum

To disable checksum offloading:

ifconfig emX -rxcsum

To confirm the current setting:

ifconfig emX

Look for the presence or absence of the following line:

options=3 <RXCSUM,TXCSUM>

TSO

The FreeBSD driver offers support for TSO (TCP Segmentation Offload). You can enable/disable it in two ways/places:

• sysctl net.inet.tcp.tso=0 (or 1 to enable it)

Doing this disables TSO in the stack and will affect all adapters.

• ifconfig emX -tso
  
  Doing this will disable TSO only for this adapter.

To enable:

• ifconfig emX tso

NOTES: By default only PCI-Express adapters are ENABLED to do TSO. Others can be enabled by the user at their own risk TSO is not supported on 82547 and 82544-based adapters, as well as older adapters.

MSI-X

The FreeBSD driver offers MSIX support with 82574L-based network connections. 82574L-based network connections will use MSI-X by default.

MSI or MSI-X can be turned off by an entry in /etc/sysctl.conf

• hw.em.enable_msi=0
  
  Unload and reload the driver.

Known Limitations

There are known performance issues with this driver when running UDP traffic with Jumbo Frames. 

82541/82547 can't link or is slow to link with some link partners

There is a known compatibility issue where time to link is slow or link is not established between 82541/82547 controllers and some switches.  Known switches include:
     Planex FXG-08TE
     I-O Data ETG-SH8

The driver can be compiled with the following changes:

Edit ./em.x.x.x/src/if_em.h to change the #define EM_MASTER_SLAVE
For example, change from:

#define EM_MASTER_SLAVE e1000_ms_hw_default
to:
#define EM_MASTER_SLAVE 2

Use one of the following options:

1 = Master mode
2 = Slave mode
3 = Auto master/slave
Setting 2 is recommended.

Recompile the module:

cd em-x.x.x
make clean
make

To install the compiled module in system directory:
make install

Support

For general information and support, go to Support

If an issue is identified, support is through email only at: freebsd@intel.com

Using the IGB Base Driver

Overview

Building and Installation

Speed and Duplex Configuration

Additional Configurations

Known Limitations

Support

Overview

This file describes the FreeBSD* driver for Intel® Ethernet. This driver has been developed for use with all community-supported versions of FreeBSD.

For questions related to hardware requirements, refer to the documentation supplied with your Gigabit adapter. All hardware requirements listed apply for use with FreeBSD.

Building and Installation

NOTE: This driver package is to be used only as a standalone archive and the user should not attempt to incorporate it into the kernel source tree.

In the instructions below, x.x.x is the driver version as indicated in the name of the driver tar file.

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

2. Untar/unzip the archive:

   tar xzvf igb-x.x.x.tar.gz

   This will create an igb-x.x.x directory.

3. To create a loadable module, perform the following steps.

   1. To compile the module
        cd igb-x.x.x
        make

   2. To install the compiled module to the system directory:
        make install

   3. If you want the driver to load automatically when the system is booted:
          1. Edit /boot/loader.conf, and add the following line.

      if_igb_load="YES"

4. To assign an IP address to the interface, enter the following:
     ifconfig_igb<interface_num> <IP_address>
    

5. 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>

6. To configure the IP address to remain after reboot, edit /etc/rc.conf, and create the appropriate ifconfig_igb<interface_num> entry:
     ifconfig_igb<interface_num>="<ifconfig_settings>"

   Example usage:
     ifconfig_igb0="inet 102.168.10.1 netmask 255.255.255.0"
    

   NOTE: For assistance, see the ifconfig man page.

Speed and Duplex Configuration

By default, the adapter auto-negotiates the speed and duplex of the connection. If there is a specific need, the ifconfig utility can be used to configure the speed and duplex settings on the adapter. Example usage:

ifconfig igbX <IP_address> media 100baseTX mediaopt full-duplex

NOTE: Only use mediaopt to set the driver to full-duplex. If mediaopt is not specified and you are not running at gigabit speed, the driver defaults to half-duplex.

If the interface is currently forced to 100 full duplex, in order to change to half duplex you must use this command:

    ifconfig igbX <IP_address> media 100baseTX -mediaopt full-duplex
 

This driver supports the following media type options:

For more information on the ifconfig utility, see the ifconfig man page.

Additional Configurations

The driver supports Transmit/Receive Checksum Offload and Jumbo Frames on all but the 82542-based adapters. For specific adapters, refer to the Identifying Your Adapter section.

Jumbo Frames

To enable Jumbo Frames, use the ifconfig utility to set the Maximum Transmission Unit (MTU) size above its default of 1500 bytes.

The Jumbo Frames MTU range for Intel Adapters is 1500 to 9216. To modify the setting, enter the following:
        ifconfig igbX <hostname or IP address> mtu 9000

To confirm the MTU used between two specific devices, use:
        route get <destination_IP_address>

NOTES: Only enable Jumbo Frames if your network infrastructure, including switches, supports them. To enable Jumbo Frames, increase the MTU size on the interface beyond 1500. The Jumbo Frames setting on the switch must be set to at least 22 bytes larger than that of the MTU.  The maximum MTU setting for Jumbo Frames is 9216. This value coincides with the maximum Jumbo Frames size of 9234 bytes. Using Jumbo Frames at 10 or 100 Mbps may result in poor performance or loss of link.

VLANs

To create a new VLAN interface:

ifconfig <vlan_name> create

To associate the VLAN interface with a physical interface and assign an IP address, netmask, and VLAN ID:

ifconfig <vlan_name> <ip_address> netmask <subnet_mask> vlan <vlan_id> vlandev <physical_interface>

Example:

ifconfig vlan10 10.0.0.1 netmask 255.255.255.0 vlan 10 vlandev igb0

In this example, all packets will be marked on egress with 802.1Q VLAN tags, specifying a VLAN ID of 10.

To remove a VLAN interface:

Intel® Network Connection       ifconfig <vlan_name> destroy

Polling

	NOTES: Device Polling is only valid for non-SMP kernels.
	The driver has to be built into the kernel for Device Polling to be enabled in the driver.

To enable polling in the driver, add the following options to the kernel configuration, and then recompile the kernel:

options DEVICE_POLLING
options HZ=1000

At runtime:
        use sysctl kern.polling.enable=1 to turn polling on

        use sysctl kern.polling.enable=0 to turn polling off

Checksum Offload

• Checksum offloading is not supported on 82542 Gigabit adapters.

• Checksum offloading supports both TCP and UDP packets and is supported for both transmit and receive.

• Checksum offloading can be enabled or disabled using ifconfig. Both transmit and receive offloading will be either enabled or disabled together. You cannot enable/disable one without the other.

To enable checksum offloading:

ifconfig igbX rxcsum

To disable checksum offloading:

ifconfig igbX -rxcsum

To confirm the current setting:

ifconfig igbX

Look for the presence or absence of the following line:

options=3 <RXCSUM,TXCSUM>

TSO

The FreeBSD driver offers support for TSO (TCP Segmentation Offload). You can enable/disable it in two ways/places:

• sysctl net.inet.tcp.tso=0 (or 1 to enable it)

Doing this disables TSO in the stack and will affect all adapters.

• ifconfig igbX -tso
  
  Doing this will disable TSO only for this adapter.

To enable:

• ifconfig igbX tso

NOTES: By default only PCI-Express adapters are ENABLED to do TSO. Others can be enabled by the user at their own risk TSO is not supported on 82547 and 82544-based adapters, as well as older adapters.

LRO

Large Receive Offload is available in the driver; it is on by default. It can be disabled by using:

ifconfig <interface_num> -lro

To enable:

ifconfig <interface_num> lro

EEE

Valid Range: 0-1
Default Value: 1 (enabled)

A link between two EEE-compliant devices will result in periodic bursts of data followed by long periods where in the link is in an idle state. This Low Power Idle (LPI) state is supported in both 1Gbps and 100Mbps link speeds.

NOTE: EEE support requires autonegotiation.

DMAC

Valid Range: 0-1
Default Value: 1 (enabled)

Enables or disables DMA Coalescing feature. DMA (Direct Memory Access) allows the network device to move packet data directly to the system's memory, reducing CPU utilitzation. 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 later. InterruptThrottleRate (ITR) should be set to dynamic. This will impart the greatest chance for your system to consume less power. DMA Coalescing is effective in helping potentially saving the platform power only when it is enabled across all active ports.

A whitepaper containing information on how to best configure your platform is available on the Intel website.

Known Limitations

There are known performance issues with this driver when running UDP traffic with Jumbo Frames. 

Support

For general information and support, go to Support

If an issue is identified, support is through email only at: freebsd@intel.com

Last modified on 8/12/11 10:34a 5/05/05 8:51a