Speed and Duplex Configuration
This file describes the Linux* Base Driver for the Intel® PRO/1000 Family of Adapters, version 5.3.x. This driver is intended for 2.4.x kernels; it is known to build properly on 2.4.x kernels through 2.4.22. Intel focused testing on Intel architectures running the 2.4.21 kernel. This driver includes support for Intel® Itanium-based systems.
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 driver. For questions related to hardware requirements, refer to the documentation supplied with your Intel PRO/1000 adapter. All hardware requirements listed apply to use with Linux.
Native VLANs are now available with supported kernels.
The driver information previously displayed in the /proc filesystem is not supported in this release. Alternatively, you can use ethtool (version 1.6 or later), lspci, and ifconfig to obtain the same information. Instructions on updating ethtool can be found in the section Additional Configurations later in this document.
For more information on how to identify your adapter, go to the Adapter & Driver ID Guide at:
For the latest Intel network drivers for Linux, refer to the following website. In the search field, enter your adapter name or type, or use the networking link on the left to search for your adapter:http://support.intel.com/support/network/adapter/pro100/21397.htm
http://downloadfinder.intel.com/scripts-df/support_intel.asp
To build a binary RPM* package of this driver, run 'rpmbuild -tb <filename.tar.gz>'. Replace <filename.tar.gz> with the specific file name of the driver.
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NOTES: 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 now. RPM functionality has only been tested in Red Hat distributions. |
Move the base driver tar file to the directory of your choice. For example, use '/home/username/e1000' or '/usr/local/src/e1000'.
Untar/unzip the archive, where <x.x.x> is the version number for the driver tar file:
tar zxf e1000-<x.x.x>.tar.gz
Change to the driver src directory, where <x.x.x> is the version number for the driver tar:
cd e1000-<x.x.x>/src/
Compile the driver module:
make install
The binary will be installed as:
/lib/modules/<kernel_version>/kernel/drivers/net/e1000.o
The install locations listed above are the default locations. They might not be correct for certain Linux distributions. For more information, go to ldistrib.htm.
Install the module:
insmod e1000 <parameter>=<value>
Assign an IP address to the interface by entering the following, where <x> is the interface number:
ifconfig eth<x> <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>
If the driver is built as a module, the following optional parameters are used by entering them on the command line with the modprobe or insmod command using this syntax:
modprobe e1000 [<option>=<VAL1>,<VAL2>,...]
insmod e1000 [<option>=<VAL1>,<VAL2>,...]
For example, with two PRO/1000 PCI adapters, entering:
insmod e1000 TxDescriptors=80,128
loads the e1000 driver with 80 TX descriptors for the first adapter and 128 TX descriptors for the second adapter.
The default value for each parameter is generally the recommended setting, unless otherwise noted.
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NOTES:
For more information about the AutoNeg, Duplex, and Speed parameters, see the Speed and Duplex
Configuration section in this document.
For more information about the InterruptThrottleRate, RxIntDelay, TxIntDelay, RxAbsIntDelay, and TxAbsIntDelay parameters, see the application note at: http://www.intel.com/design/network/applnots/ap450.htm. A descriptor describes a data buffer and attributes related to the data buffer. This information is accessed by the hardware. |
Parameter Name | Valid Range/Settings | Default | Description |
---|---|---|---|
AutoNeg | 0x01-0x0F, 0x20-0x2F | 0x2F |
This parameter is a bit mask that specifies which speed and duplex
settings the board advertises. When this parameter is used, the
Speed and Duplex parameters must not be specified.
(adapters using copper connections only) |
Duplex | 0-2 (0=auto-negotiate, 1=half, 2=full) | 0 |
Defines the direction in which data is allowed to flow. Can be either
one or two-directional. If both Duplex and the link partner are set to auto-negotiate, the board
auto-detects the correct duplex. If the link partner is forced
(either full or half), Duplex defaults to half-duplex.
(adapters using copper connections only) |
FlowControl | 0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx) | Read flow control settings from the EEPROM | This parameter controls the automatic generation(Tx) and response(Rx) to Ethernet PAUSE frames. |
InterruptThrottleRate | 100-100000 (0=off, 1=dynamic) | 1 | This value represents the maximum number of
interrupts per second the controller generates. InterruptThrottleRate is
another setting used in interrupt moderation. Dynamic mode uses a
heuristic algorithm to adjust InterruptThrottleRate based on the current
traffic load.
Un-supported Adapters: InterruptThrottleRate is not supported by 82542, 82543, 82545, or 82544-based adapters. NOTE: InterruptThrottleRate takes precedence over the TxAbsIntDelay and RxAbsIntDelay parameters. In other words, minimizing the receive and/or transmit absolute delays does not force the controller to generate more interrupts than what the Interrupt Throttle Rate allows.
CAUTION: If you are using the Intel PRO/1000 CT
Network Connection (controller 82547), setting InterruptThrottleRate to a
value
NOTE: When e1000 is loaded with default settings and
multiple adapters are in use simultaneously, the CPU utilization may
increase non-linearly. In order to limit the CPU utilization without
impacting the overall throughput, we recommend that you load the driver as
follows: |
RxDescriptors | 80-256 for 82542 and 82543-based adapters
80-4096 for all other supported adapters |
256 |
This value is the number of receive descriptors allocated by the
driver. Increasing this value allows the driver to buffer more
incoming packets. Each descriptor is 16 bytes. A receive buffer is
also allocated for each descriptor and can be either 2048, 4096, 8192,
or 16384 bytes, depending on the MTU setting. The maximum MTU size is 16110. NOTE: MTU designates the frame size. It only needs to be set for Jumbo Frames.
NOTE: Depending on the available system resources, the request
for a |
RxIntDelay | 0-65535 (0=off) | 0 |
This value delays the generation of receive interrupts in units of
1.024 microseconds. Receive interrupt reduction can improve CPU
efficiency if properly tuned for specific network traffic.
Increasing this value adds extra latency to frame reception
and can end up decreasing the throughput of TCP traffic. If the system is
reporting dropped receives, this value may be set too high, causing the
driver to run out of available receive descriptors.
CAUTION: When setting RxIntDelay to a value other than 0, adapters may hang (stop transmitting) under certain network conditions. If this occurs a NETDEV WATCHDOG message is logged in the system event log. In addition, the controller is automatically reset, restoring the network connection. To eliminate the potential for the hang ensure that RxIntDelay is set to zero. |
RxAbsIntDelay | 0-65535 (0=off) | 128 | This value, in units of 1.024 microseconds, limits the delay in which a
receive interrupt is generated. Useful only if RxIntDelay is non-zero,
this value ensures that an interrupt is generated after the initial
packet is received within the set amount of time. Proper tuning,
along with RxIntDelay, may improve traffic throughput in specific
network conditions.
(82540, 82545, and later adapters only) |
Speed | 0, 10, 100, 1000 | 0 |
Speed forces the line speed to the specified value in megabits per second (Mbps). If this parameter
is not specified or is set to 0 and the link partner is set to auto-negotiate, the board
will auto-detect the correct speed. Duplex must also be set when Speed is set to either 10 or 100. (adapters using copper connections only) |
TxDescriptors | 80-256 for 82542 and 82543-based adapters
80-4096 for all other supported adapters |
256 | This value is the number of transmit descriptors allocated by the driver. Increasing this value allows the driver to queue more transmits. Each descriptor is 16 bytes. |
TxIntDelay | 0-65535 (0=off) | 64 | This value delays the generation of transmit interrupts in units of 1.024 microseconds. Transmit interrupt reduction can improve CPU efficiency if properly tuned for specific network traffic. If the system is reporting dropped transmits, this value may be set too high causing the driver to run out of available transmit descriptors. |
TxAbsIntDelay | 0-65535 (0=off) | 64 |
This value, in units of 1.024 microseconds, limits the delay in which a transmit interrupt is generated. Useful only if TxIntDelay is non-zero, this value ensures that an interrupt is generated after the initial packet is sent on the wire within the set amount of time. Proper tuning, along with TxIntDelay, may improve traffic throughput in specific network conditions. (82540, 82545, and later adapters only) |
XsumRX | 0-1 | 1 |
A value of '1' indicates that the driver should enable IP checksum offload for received packets (both UDP and TCP) to the adapter hardware. (not available on the 82542-based adapter) |
Three keywords are used to control the speed and duplex configuration. These keywords are Speed, Duplex, and AutoNeg.
If the board uses a fiber interface, these keywords are ignored, and the fiber interface board only links at 1000 Mbps full-duplex.
For copper-based boards, the keywords interact as follows:
The default operation is auto-negotiate. The board advertises all supported speed and duplex combinations, and it links at the highest common speed and duplex mode IF the link partner is set to auto-negotiate.
If Speed = 1000, limited auto-negotiation is enabled and only 1000 Mbps is advertised (The 1000BaseT spec requires auto-negotiation.)
If Speed = 10 or 100, then both Speed and Duplex should be set. Auto-negotiation is disabled, and the AutoNeg parameter is ignored. Partner SHOULD also be forced.
The AutoNeg parameter is used when more control is required over the auto-negotiation process. When this parameter is used, Speed and Duplex must not be specified. This parameter is a bitmap that specifies which speed and duplex settings are advertised to the link partner.
Bit: | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Speed (Mbps): | N/A | N/A | 1000 | N/A | 100 | 100 | 10 | 10 |
Duplex: | Full | Full | Half | Full | Half |
Note that setting AutoNeg does not guarantee that the board will link at the highest specified speed or duplex mode, but the board will link at the highest possible speed/duplex of the link partner IF the link partner is also set to auto-negotiate. If the link partner is forced speed/duplex, the adapter MUST be forced to the same speed/duplex.
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 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 Linux Base Driver for the Intel PRO/1000 family of adapters is e1000.
As an example, if you install the e1000 driver for two PRO/1000 adapters (eth0 and eth1) and set the speed and duplex to 10full and 100half, add the following to modules.conf:
alias eth0 e1000
alias eth1 e1000
options e1000 Speed=10,100 Duplex=2,1
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
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NOTE: This setting is not saved across reboots. |
The driver supports Jumbo Frames for all adapters except 82542-based adapters. Jumbo Frames support is enabled by changing the MTU to a value larger than the default of 1500. Use the ifconfig command to increase the MTU size. For example:
ifconfig eth<x> mtu 9000 up
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NOTE: This setting is not saved across reboots. The
setting change can be made permanent by adding:
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The maximum MTU setting for Jumbo Frames is 16110. This value coincides with the maximum Jumbo Frames size of 16128.
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NOTES: Jumbo Frames are
supported at 1000 Mbps only. Using Jumbo Frames at 10 or 100 Mbps may result
in poor performance or loss of link. MTU designates the frame size. To enable Jumbo Frames increase the MTU size on the interface beyond 1500. |
The driver utilizes the ethtool interface for driver configuration and diagnostics, as well as displaying statistical information. Ethtool version 1.6 or later is required for this functionality.
The latest release of ethtool can be found at: http://sourceforge.net/projects/gkernel. After ethtool is installed, ethtool-copy.h must be copied and renamed to ethtool.h in your kernel source tree at <linux_kernel_src>/include/linux. Backup the original ethtool.h as needed before copying. The driver then must be recompiled in order to take advantage of the latest ethtool features.
WoL is configured through the Ethtool* utility. Ethtool is included with all versions of Red Hat after Red Hat 7.2. For other Linux distributions, download and install Ethtool from the following website: http://sourceforge.net/projects/gkernel.
For instructions on enabling WoL with Ethtool, refer to the website listed above.
WoL will be enabled on the system during the next shut down or reboot. For this driver version, in order to enable WoL, the e1000 driver must be loaded prior to shutting down or suspending the system.
NAPI (Rx polling mode) is supported in the e1000 driver. NAPI is enabled or disabled based on the configuration of the kernel. To override the default, use the following compile-time flags.
To enable NAPI, compile the driver module, passing in a configuration option:
make CFLAGS_EXTRA=-DE1000_NAPI install
To disable NAPI, compile the driver module, passing in a configuration option:
make CFLAGS_EXTRA=-DE1000_NO_NAPI install
See http://www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI.
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NOTE: For distribution-specific information, see ldistrib.htm. |
When trying to compile the driver by running make install, the following error may occur: "Linux kernel source not configured - missing version.h"
To solve this issue, create the version.h file by going to the Linux source tree and entering:
make include/linux/version.h
Memory allocation failures have been observed on Linux systems with 64 MB of RAM or less that are running Jumbo Frames. If you are using Jumbo Frames, your system may require more than the advertised minimum requirement of 64 MB of system memory.
Degradation in throughput performance may be observed in some Jumbo frames environments. If this is observed, increasing the application's socket buffer size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values may help. See the specific application manual and /usr/src/linux*/Documentation/networking/ip-sysctl.txt for more details.
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, either turn on ARP filtering by entering:
echo 1 > /proc/sys/net/ipv4/conf/all/arp_filter
(this only works if your kernel's version is higher than 2.4.5),
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NOTE: This setting is not saved across reboots. The
configuration change can be made permanent by adding the line:
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There is a known compatibility issue with 82541/82547 and some low-end
switches where the link will not be established, or will
be slow to establish. In particular, these switches are known to be incompatible
with 82541/82547:
Planex FXG-08TE
I-O Data ETG-SH8
To workaround this issue, the driver can be compiled with an override of the
PHY's master/slave setting. Forcing master or forcing slave
mode will improve time-to-link.
# make CFLAGS_EXTRA=-DE1000_MASTER_SLAVE=<n>
Where <n> is:
0 = Hardware default
1 = Master mode
2 = Slave mode
3 = Auto master/slave
In order to disable receive flow control using ethtool on the following
adapters, you must turn off auto-negotiation on the same command line.
For example:
ethtool -A
eth? autoneg off rx off
Intel PRO/1000 MT Network Connection
Intel PRO/1000 MT Desktop Adapter
Intel PRO/1000 CT Desktop Adapter
Intel PRO/1000 CT Desktop Adapter
Intel PRO/1000 CT Mobile Connection
Last modified on 6/23/04 1:08p Revision 18