# FreeBSD* Driver for the Intel® PRO/1000 Family of Adapters

Overview

Identifying Your Adapter

Building and Installation

Speed and Duplex Configuration

Additional Configurations

Known Limitations

Support

## Overview

This file describes the FreeBSD* driver for the Intel® PRO/1000 Family of Adapters. This driver has been developed for use with FreeBSD, Release 4.10 and greater and Release 5.4.

For questions related to hardware requirements, refer to the documentation supplied with your Intel PRO/1000 adapter. All hardware requirements listed apply for use with FreeBSD.

## Identifying Your Adapter

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

> http://support.intel.com/support/network/adapter/pro100/21397.htm

For the latest Intel network drivers for FreeBSD, see:

> http://downloadfinder.intel.com/scripts-df-external/support_intel.aspx

| NOTE: Mobile adapters are not fully supported.

## Building and Installation

| NOTE: The driver can be installed as a dynamic loadable kernel module or compiled into the kernel. You must have kernel sources installed in order to compile the driver module.

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 xvfz 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.

   | NOTE: To compile the driver into the kernel, proceed to step 4.

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

   2. To install the compiled module in 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 compile the driver into the kernel, enter:
   cd em-x.x.x/src
   cp if_em* /usr/src/sys/dev/em
   cp Makefile.kernel /usr/src/sys/modules/em/Makefile

   Edit the /usr/src/sys/conf/files.i386 file, and add the following lines only if they do not already exist:
   dev/em/if_em.c optional em
   dev/em/if_em_hw.c optional em

   Remove the following lines from the /usr/src/sys/conf/files.i386 file, if they exist:
   dev/em/if_em_hw.c optional em
   dev/em/if_em_phy.c optional em

   Edit the kernel configuration file (i.e., GENERIC or MYKERNEL) in /usr/src/sys/i386/conf, and ensure the following line is present:
   device em

   Compile and install the kernel. The system must be rebooted for the kernel updates to take effect. For additional information on compiling the kernel, consult the FreeBSD operating system documentation.

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

6. 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>

7. 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 em<interface_num> <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.

This driver supports the following media type options:

Media Type | Description
--- | ---
autoselect | Enables auto-negotiation for speed and duplex.
10baseT/UTP | Sets speed to 10 Mbps. Use the ifconfig mediaopt option to select full-duplex mode.
100baseTX | Sets speed to 100 Mbps. Use the ifconfig mediaopt option to select full-duplex mode.
1000baseTX | Sets speed to 1000 Mbps. In this case, the driver supports only full-duplex mode.
1000baseSX | Sets speed to 1000 Mbps. In this case, the driver supports only full-duplex mode.

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 em<interface_num> <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 and 82572EI controllers, which correspond to these product names:
  Intel® PRO/1000 PT Dual Port Server Adapter
  Intel® PRO/1000 PF Dual Port Server Adapter
  Intel® PRO/1000 PT Server Adapter
  Intel® PRO/1000 PT Desktop Adapter
  Intel® PRO/1000 PF Server Adapter

- Using Jumbo Frames at 10 or 100 Mbps may result in poor performance or loss of link.

- The Intel PRO/1000 PM Network Connection does not support jumbo frames.

### 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 vlan10 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 <interface_num> rxcsum

To disable checksum offloading:

> ifconfig <interface_num> -rxcsum

To confirm the current setting:

> ifconfig <interface_num>

Look for the presence or absence of the following line:

> options=3 <RXCSUM,TXCSUM>

## 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
To improve time to link, the driver can be compiled with the following changes:

Edit ./em.x.x.x/src/if_em.h to uncomment the #define EM_MASTER_SLAVE from within the comments. For example:
Find this: /* #define EM_MASTER_SLAVE 2 */
Replace with this: #define EM_MASTER_SLAVE 2

Using one of the following options:
1 = Master mode
2 = Slave mode
3 = Auto master/slave

Option 2 is the recommended setting.
Recompile the module:

> cd em-x.x.x
> make clean
> make

Install the compiled module in system directory:

> make install

## Support

For general information and support, go to http://support.intel.com

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

`Last modified on 9/19/05 3:02p 5/05/05 8:51a 19`