|  | Linux* Base Driver for the Intel(R) PRO/1000 Family of Adapters | 
|  | =============================================================== | 
|  |  | 
|  | September 26, 2006 | 
|  |  | 
|  |  | 
|  | Contents | 
|  | ======== | 
|  |  | 
|  | - In This Release | 
|  | - Identifying Your Adapter | 
|  | - Building and Installation | 
|  | - Command Line Parameters | 
|  | - Speed and Duplex Configuration | 
|  | - Additional Configurations | 
|  | - Known Issues | 
|  | - Support | 
|  |  | 
|  |  | 
|  | In This Release | 
|  | =============== | 
|  |  | 
|  | This file describes the Linux* Base Driver for the Intel(R) PRO/1000 Family | 
|  | of Adapters.  This driver includes support for Itanium(R)2-based systems. | 
|  |  | 
|  | 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. | 
|  |  | 
|  | The following features are now available in supported kernels: | 
|  | - Native VLANs | 
|  | - Channel Bonding (teaming) | 
|  | - SNMP | 
|  |  | 
|  | Channel Bonding documentation can be found in the Linux kernel source: | 
|  | /Documentation/networking/bonding.txt | 
|  |  | 
|  | 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. | 
|  |  | 
|  | NOTE: The Intel(R) 82562v 10/100 Network Connection only provides 10/100 | 
|  | support. | 
|  |  | 
|  |  | 
|  | Identifying Your Adapter | 
|  | ======================== | 
|  |  | 
|  | For more 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 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://downloadfinder.intel.com/scripts-df/support_intel.asp | 
|  |  | 
|  |  | 
|  | Command Line Parameters | 
|  | ======================= | 
|  |  | 
|  | If the driver is built as a module, the  following optional parameters | 
|  | are used by entering them on the command line with the modprobe command | 
|  | using this syntax: | 
|  |  | 
|  | modprobe e1000 [<option>=<VAL1>,<VAL2>,...] | 
|  |  | 
|  | For example, with two PRO/1000 PCI adapters, entering: | 
|  |  | 
|  | modprobe 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. | 
|  |  | 
|  | 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. | 
|  |  | 
|  |  | 
|  | AutoNeg | 
|  | ------- | 
|  | (Supported only on adapters with copper connections) | 
|  | Valid Range:   0x01-0x0F, 0x20-0x2F | 
|  | Default Value: 0x2F | 
|  |  | 
|  | This parameter is a bit-mask that specifies the speed and duplex settings | 
|  | advertised by the adapter.  When this parameter is used, the Speed and | 
|  | Duplex parameters must not be specified. | 
|  |  | 
|  | NOTE:  Refer to the Speed and Duplex section of this readme for more | 
|  | information on the AutoNeg parameter. | 
|  |  | 
|  |  | 
|  | Duplex | 
|  | ------ | 
|  | (Supported only on adapters with copper connections) | 
|  | Valid Range:   0-2 (0=auto-negotiate, 1=half, 2=full) | 
|  | Default Value: 0 | 
|  |  | 
|  | This 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. | 
|  |  | 
|  |  | 
|  | FlowControl | 
|  | ----------- | 
|  | Valid Range:   0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx) | 
|  | Default Value: Reads flow control settings from the EEPROM | 
|  |  | 
|  | This parameter controls the automatic generation(Tx) and response(Rx) | 
|  | to Ethernet PAUSE frames. | 
|  |  | 
|  |  | 
|  | InterruptThrottleRate | 
|  | --------------------- | 
|  | (not supported on Intel(R) 82542, 82543 or 82544-based adapters) | 
|  | Valid Range:   0,1,3,100-100000 (0=off, 1=dynamic, 3=dynamic conservative) | 
|  | Default Value: 3 | 
|  |  | 
|  | The driver can limit the amount of interrupts per second that the adapter | 
|  | will generate for incoming packets. It does this by writing a value to the | 
|  | adapter that is based on the maximum amount of interrupts that the adapter | 
|  | will generate per second. | 
|  |  | 
|  | Setting InterruptThrottleRate to a value greater or equal to 100 | 
|  | will program the adapter to send out a maximum of 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. | 
|  |  | 
|  | The default behaviour of the driver previously assumed a static | 
|  | InterruptThrottleRate value of 8000, providing a good fallback value for | 
|  | all traffic types,but lacking in small packet performance and latency. | 
|  | The hardware can handle many more small packets per second however, and | 
|  | for this reason an adaptive interrupt moderation algorithm was implemented. | 
|  |  | 
|  | Since 7.3.x, the driver has two adaptive modes (setting 1 or 3) in which | 
|  | it dynamically adjusts the InterruptThrottleRate value based on the traffic | 
|  | that it receives. After determining the type of incoming traffic in the last | 
|  | timeframe, it will adjust the InterruptThrottleRate to an appropriate value | 
|  | for that traffic. | 
|  |  | 
|  | The algorithm classifies the incoming traffic every interval into | 
|  | classes.  Once the class is determined, the InterruptThrottleRate value is | 
|  | adjusted to suit that traffic type the best. There are three classes defined: | 
|  | "Bulk traffic", for large amounts of packets of normal size; "Low latency", | 
|  | for small amounts of traffic and/or a significant percentage of small | 
|  | packets; and "Lowest latency", for almost completely small packets or | 
|  | minimal traffic. | 
|  |  | 
|  | In dynamic conservative mode, the InterruptThrottleRate value is set to 4000 | 
|  | for traffic that falls in class "Bulk traffic". If traffic falls in the "Low | 
|  | latency" or "Lowest latency" class, the InterruptThrottleRate is increased | 
|  | stepwise to 20000. This default mode is suitable for most applications. | 
|  |  | 
|  | For situations where low latency is vital such as cluster or | 
|  | grid computing, the algorithm can reduce latency even more when | 
|  | InterruptThrottleRate is set to mode 1. In this mode, which operates | 
|  | the same as mode 3, the InterruptThrottleRate will be increased stepwise to | 
|  | 70000 for traffic in class "Lowest latency". | 
|  |  | 
|  | Setting InterruptThrottleRate to 0 turns off any interrupt moderation | 
|  | and may improve small packet latency, but is generally not suitable | 
|  | for bulk throughput traffic. | 
|  |  | 
|  | 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(R) PRO/1000 CT Network Connection | 
|  | (controller 82547), setting InterruptThrottleRate to a value | 
|  | greater than 75,000, may hang (stop transmitting) adapters | 
|  | 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 InterruptThrottleRate is set no greater | 
|  | than 75,000 and is not set to 0. | 
|  |  | 
|  | 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: | 
|  |  | 
|  | modprobe e1000 InterruptThrottleRate=3000,3000,3000 | 
|  |  | 
|  | This sets the InterruptThrottleRate to 3000 interrupts/sec for | 
|  | the first, second, and third instances of the driver.  The range | 
|  | of 2000 to 3000 interrupts per second works on a majority of | 
|  | systems and is a good starting point, but the optimal value will | 
|  | be platform-specific.  If CPU utilization is not a concern, use | 
|  | RX_POLLING (NAPI) and default driver settings. | 
|  |  | 
|  |  | 
|  |  | 
|  | RxDescriptors | 
|  | ------------- | 
|  | Valid Range:   80-256 for 82542 and 82543-based adapters | 
|  | 80-4096 for all other supported adapters | 
|  | Default Value: 256 | 
|  |  | 
|  | This value specifies the number of receive buffer descriptors allocated | 
|  | by the driver.  Increasing this value allows the driver to buffer more | 
|  | incoming packets, at the expense of increased system memory utilization. | 
|  |  | 
|  | 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.  Depending on the available system resources, the request | 
|  | for a higher number of receive descriptors may be denied.  In this | 
|  | case, use a lower number. | 
|  |  | 
|  |  | 
|  | RxIntDelay | 
|  | ---------- | 
|  | Valid Range:   0-65535 (0=off) | 
|  | Default Value: 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 0. | 
|  |  | 
|  |  | 
|  | RxAbsIntDelay | 
|  | ------------- | 
|  | (This parameter is supported only on 82540, 82545 and later adapters.) | 
|  | Valid Range:   0-65535 (0=off) | 
|  | Default Value: 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. | 
|  |  | 
|  |  | 
|  | Speed | 
|  | ----- | 
|  | (This parameter is supported only on adapters with copper connections.) | 
|  | Valid Settings: 0, 10, 100, 1000 | 
|  | Default Value:  0 (auto-negotiate at all supported speeds) | 
|  |  | 
|  | 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 should also be set when Speed is set to either 10 or 100. | 
|  |  | 
|  |  | 
|  | TxDescriptors | 
|  | ------------- | 
|  | Valid Range:   80-256 for 82542 and 82543-based adapters | 
|  | 80-4096 for all other supported adapters | 
|  | Default Value: 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. | 
|  |  | 
|  | NOTE:  Depending on the available system resources, the request for a | 
|  | higher number of transmit descriptors may be denied.  In this case, | 
|  | use a lower number. | 
|  |  | 
|  |  | 
|  | TxIntDelay | 
|  | ---------- | 
|  | Valid Range:   0-65535 (0=off) | 
|  | Default Value: 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 | 
|  | ------------- | 
|  | (This parameter is supported only on 82540, 82545 and later adapters.) | 
|  | Valid Range:   0-65535 (0=off) | 
|  | Default Value: 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. | 
|  |  | 
|  | XsumRX | 
|  | ------ | 
|  | (This parameter is NOT supported on the 82542-based adapter.) | 
|  | Valid Range:   0-1 | 
|  | Default Value: 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. | 
|  |  | 
|  |  | 
|  | Speed and Duplex Configuration | 
|  | ============================== | 
|  |  | 
|  | 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.  It should be used when you wish to control which | 
|  | speed and duplex combinations are advertised during the auto-negotiation | 
|  | process. | 
|  |  | 
|  | The parameter may be specified as either a decimal or hexadecimal value as | 
|  | determined by the bitmap below. | 
|  |  | 
|  | Bit position   7      6      5       4       3      2      1       0 | 
|  | Decimal Value  128    64     32      16      8      4      2       1 | 
|  | Hex value      80     40     20      10      8      4      2       1 | 
|  | Speed (Mbps)   N/A    N/A    1000    N/A     100    100    10      10 | 
|  | Duplex                       Full            Full   Half   Full    Half | 
|  |  | 
|  | Some examples of using AutoNeg: | 
|  |  | 
|  | modprobe e1000 AutoNeg=0x01 (Restricts autonegotiation to 10 Half) | 
|  | modprobe e1000 AutoNeg=1 (Same as above) | 
|  | modprobe e1000 AutoNeg=0x02 (Restricts autonegotiation to 10 Full) | 
|  | modprobe e1000 AutoNeg=0x03 (Restricts autonegotiation to 10 Half or 10 Full) | 
|  | modprobe e1000 AutoNeg=0x04 (Restricts autonegotiation to 100 Half) | 
|  | modprobe e1000 AutoNeg=0x05 (Restricts autonegotiation to 10 Half or 100 | 
|  | Half) | 
|  | modprobe e1000 AutoNeg=0x020 (Restricts autonegotiation to 1000 Full) | 
|  | modprobe e1000 AutoNeg=32 (Same as above) | 
|  |  | 
|  | Note that when this parameter is used, Speed and Duplex must not be specified. | 
|  |  | 
|  | If the link partner is forced to a specific speed and duplex, then this | 
|  | parameter should not be used.  Instead, use the Speed and Duplex parameters | 
|  | previously mentioned to force the adapter to the same speed and duplex. | 
|  |  | 
|  |  | 
|  | Additional Configurations | 
|  | ========================= | 
|  |  | 
|  | 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 Linux Base Driver | 
|  | for the Intel(R) 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 or or modprobe.conf: | 
|  |  | 
|  | alias eth0 e1000 | 
|  | alias eth1 e1000 | 
|  | options e1000 Speed=10,100 Duplex=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 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 | 
|  |  | 
|  | This setting is not saved across reboots.  It can be made permanent if | 
|  | you add: | 
|  |  | 
|  | MTU=9000 | 
|  |  | 
|  | to the file /etc/sysconfig/network-scripts/ifcfg-eth<x>.  This example | 
|  | applies to the Red Hat distributions; other distributions may store this | 
|  | setting in a different location. | 
|  |  | 
|  | Notes: | 
|  |  | 
|  | - To enable Jumbo Frames, increase the MTU size on the interface beyond | 
|  | 1500. | 
|  |  | 
|  | - The maximum MTU setting for Jumbo Frames is 16110.  This value coincides | 
|  | with the maximum Jumbo Frames size of 16128. | 
|  |  | 
|  | - Using Jumbo Frames at 10 or 100 Mbps may result in poor performance or | 
|  | loss of link. | 
|  |  | 
|  | - 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(R) 82571EB, | 
|  | 82572EI, 82573L and 80003ES2LAN controller.  These correspond to the | 
|  | following product names: | 
|  | Intel(R) PRO/1000 PT Server Adapter | 
|  | Intel(R) PRO/1000 PT Desktop Adapter | 
|  | Intel(R) PRO/1000 PT Network Connection | 
|  | Intel(R) PRO/1000 PT Dual Port Server Adapter | 
|  | Intel(R) PRO/1000 PT Dual Port Network Connection | 
|  | Intel(R) PRO/1000 PF Server Adapter | 
|  | Intel(R) PRO/1000 PF Network Connection | 
|  | Intel(R) PRO/1000 PF Dual Port Server Adapter | 
|  | Intel(R) PRO/1000 PB Server Connection | 
|  | Intel(R) PRO/1000 PL Network Connection | 
|  | Intel(R) PRO/1000 EB Network Connection with I/O Acceleration | 
|  | Intel(R) PRO/1000 EB Backplane Connection with I/O Acceleration | 
|  | Intel(R) PRO/1000 PT Quad Port Server Adapter | 
|  |  | 
|  | - Adapters based on the Intel(R) 82542 and 82573V/E controller do not | 
|  | support Jumbo Frames. These correspond to the following product names: | 
|  | Intel(R) PRO/1000 Gigabit Server Adapter | 
|  | Intel(R) PRO/1000 PM Network Connection | 
|  |  | 
|  | - The following adapters do not support Jumbo Frames: | 
|  | Intel(R) 82562V 10/100 Network Connection | 
|  | Intel(R) 82566DM Gigabit Network Connection | 
|  | Intel(R) 82566DC Gigabit Network Connection | 
|  | Intel(R) 82566MM Gigabit Network Connection | 
|  | Intel(R) 82566MC Gigabit Network Connection | 
|  | Intel(R) 82562GT 10/100 Network Connection | 
|  | Intel(R) 82562G 10/100 Network Connection | 
|  |  | 
|  |  | 
|  | Ethtool | 
|  | ------- | 
|  | 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 from | 
|  | http://sourceforge.net/projects/gkernel. | 
|  |  | 
|  | NOTE: Ethtool 1.6 only supports a limited set of ethtool options.  Support | 
|  | for a more complete ethtool feature set can be enabled by upgrading | 
|  | ethtool to ethtool-1.8.1. | 
|  |  | 
|  | Enabling Wake on LAN* (WoL) | 
|  | --------------------------- | 
|  | 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 when shutting down or rebooting the system. | 
|  |  | 
|  | Wake On LAN is only supported on port A for the following devices: | 
|  | Intel(R) PRO/1000 PT Dual Port Network Connection | 
|  | Intel(R) PRO/1000 PT Dual Port Server Connection | 
|  | Intel(R) PRO/1000 PT Dual Port Server Adapter | 
|  | Intel(R) PRO/1000 PF Dual Port Server Adapter | 
|  | Intel(R) PRO/1000 PT Quad Port Server Adapter | 
|  |  | 
|  | NAPI | 
|  | ---- | 
|  | NAPI (Rx polling mode) is enabled in the e1000 driver. | 
|  |  | 
|  | See www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI. | 
|  |  | 
|  |  | 
|  | Known Issues | 
|  | ============ | 
|  |  | 
|  | Dropped Receive Packets on Half-duplex 10/100 Networks | 
|  | ------------------------------------------------------ | 
|  | If you have an Intel PCI Express adapter running at 10mbps or 100mbps, half- | 
|  | duplex, you may observe occasional dropped receive packets.  There are no | 
|  | workarounds for this problem in this network configuration.  The network must | 
|  | be updated to operate in full-duplex, and/or 1000mbps only. | 
|  |  | 
|  | Jumbo Frames System Requirement | 
|  | ------------------------------- | 
|  | 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. | 
|  |  | 
|  | Performance Degradation with Jumbo Frames | 
|  | ----------------------------------------- | 
|  | 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. | 
|  |  | 
|  | Jumbo Frames on Foundry BigIron 8000 switch | 
|  | ------------------------------------------- | 
|  | There is a known issue using Jumbo frames when connected to a Foundry | 
|  | BigIron 8000 switch.  This is a 3rd party limitation.  If you experience | 
|  | loss of packets, lower the MTU size. | 
|  |  | 
|  | Allocating Rx Buffers when Using Jumbo Frames | 
|  | --------------------------------------------- | 
|  | Allocating Rx buffers when using Jumbo Frames on 2.6.x kernels may fail if | 
|  | the available memory is heavily fragmented. This issue may be seen with PCI-X | 
|  | adapters or with packet split disabled. This can be reduced or eliminated | 
|  | by changing the amount of available memory for receive buffer allocation, by | 
|  | increasing /proc/sys/vm/min_free_kbytes. | 
|  |  | 
|  | 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, 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), | 
|  |  | 
|  | NOTE: This setting is not saved across reboots.  The configuration | 
|  | change can be made permanent by adding the line: | 
|  | net.ipv4.conf.all.arp_filter = 1 | 
|  | to the file /etc/sysctl.conf | 
|  |  | 
|  | or, | 
|  |  | 
|  | install the interfaces in separate broadcast domains (either in | 
|  | different switches or in a switch partitioned to VLANs). | 
|  |  | 
|  | 82541/82547 can't link or are slow to link with some link partners | 
|  | ----------------------------------------------------------------- | 
|  | 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 | 
|  |  | 
|  | Disable rx flow control with ethtool | 
|  | ------------------------------------ | 
|  | In order to disable receive flow control using ethtool, you must turn | 
|  | off auto-negotiation on the same command line. | 
|  |  | 
|  | For example: | 
|  |  | 
|  | ethtool -A eth? autoneg off rx off | 
|  |  | 
|  | Unplugging network cable while ethtool -p is running | 
|  | ---------------------------------------------------- | 
|  | In kernel versions 2.5.50 and later (including 2.6 kernel), unplugging | 
|  | the network cable while ethtool -p is running will cause the system to | 
|  | become unresponsive to keyboard commands, except for control-alt-delete. | 
|  | Restarting the system appears to be the only remedy. | 
|  |  | 
|  |  | 
|  | Support | 
|  | ======= | 
|  |  | 
|  | For general information, go to the Intel support website at: | 
|  |  | 
|  | http://support.intel.com | 
|  |  | 
|  | or the Intel Wired Networking project hosted by Sourceforge at: | 
|  |  | 
|  | http://sourceforge.net/projects/e1000 | 
|  |  | 
|  | If an issue is identified with the released source code on the supported | 
|  | kernel with a supported adapter, email the specific information related | 
|  | to the issue to e1000-devel@lists.sf.net |