Speed and Duplex Configuration
This file describes the FreeBSD* driver for the Gigabit Family of Adapters. This driver has been developed for use with FreeBSD, Release 6.x.
For questions related to hardware requirements, refer to the documentation supplied with your Gigabit adapter. All hardware requirements listed apply for use with FreeBSD.
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
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NOTE: Mobile adapters are not fully supported. |
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NOTE: The Intel® 82562v 10/100 Network Connection only supports 10/100 connectivity. |
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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.
Move the base driver tar file to the directory of your choice. For example, use /home/username/em or /usr/local/src/em.
Untar/unzip the archive:
tar zvfz em-x.x.x.tar.gz
This will create an em-x.x.x directory.
To create a loadable module, perform the following steps.
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NOTE: To compile the driver into the kernel, proceed to step 4. |
To compile the module
cd em-x.x.x
make
To install the compiled module to the system
directory:
make install
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"
To compile the driver into the kernel, enter:
cd em-x.x.x/src
cp *.[ch] /usr/src/sys/dev/em
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NOTE: At this point you MUST install a patch, kernbuild.patch, which is located in the patches directory. This is applied as shown below where “$PATH_TO_KERNBUILD_PATCH” is the location of the kernbuild.patch: cd /usr/src/sys; patch –p1 < $PATH_TO_KERNBUILD_PATCH |
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.
To assign an IP address to the interface, enter the following:
ifconfig_em<interface_num> <IP_address>
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>
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"
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NOTE: For assistance, see the ifconfig man page. |
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
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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 em<interface_num> <IP_address>
media 100baseTX -mediaopt full-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.
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.
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>
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NOTES:
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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
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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 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>
The FreeBSD driver now offers support for TSO (TCP Segmentation Offload). To
enable this support perform the following:
Patch the kernel with the patch supplied in the tarball.
Rebuild and install the kernel.
Recompile the driver. You must alter the Makefile to build the driver with
EM_TSO defined.
Enable or disable TSO:
sysctl net.inet.tcp.tso=1 or 0
0=disabled, 1=enabled (TSO is enabled by default).
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NOTE: TSO is not supported on 82547 and 82544-based adapters, as well as older adapters. |
In some cases ports 3 and 4 won’t pass traffic. Ports 1 and 2 don't show any errors and will pass traffic.
This issue MAY be resolved by updating to the latest BIOS. You can check your system's BIOS by downloading the Linux Firmware Developer Kit that can be obtained at http://www.linuxfirmwarekit.org/
In FreeBSD version 4.x with Symmetric MultiProcessing (SMP), there is a known issue on some newer hardware. The problem is kernel generic and only in SMP mode. The workaround is to either use FreeBSD version 4.x in single processor mode, or use FreeBSD 5.4 or later.
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
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 4/03/07 11:45a 5/05/05 8:51a 39