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Based on kernel version 2.6.34. Page generated on 2010-05-31 16:03 EST.

1	Linux* Base Driver for the Intel(R) PRO/1000 Family of Adapters
2	===============================================================
3	
4	September 26, 2006
5	
6	
7	Contents
8	========
9	
10	- In This Release
11	- Identifying Your Adapter
12	- Building and Installation
13	- Command Line Parameters
14	- Speed and Duplex Configuration
15	- Additional Configurations
16	- Known Issues
17	- Support
18	
19	
20	In This Release
21	===============
22	
23	This file describes the Linux* Base Driver for the Intel(R) PRO/1000 Family
24	of Adapters.  This driver includes support for Itanium(R)2-based systems.
25	
26	For questions related to hardware requirements, refer to the documentation
27	supplied with your Intel PRO/1000 adapter. All hardware requirements listed
28	apply to use with Linux.
29	
30	The following features are now available in supported kernels:
31	 - Native VLANs
32	 - Channel Bonding (teaming)
33	 - SNMP
34	
35	Channel Bonding documentation can be found in the Linux kernel source:
36	/Documentation/networking/bonding.txt
37	
38	The driver information previously displayed in the /proc filesystem is not
39	supported in this release.  Alternatively, you can use ethtool (version 1.6
40	or later), lspci, and ifconfig to obtain the same information.
41	
42	Instructions on updating ethtool can be found in the section "Additional
43	Configurations" later in this document.
44	
45	NOTE: The Intel(R) 82562v 10/100 Network Connection only provides 10/100
46	support.
47	
48	
49	Identifying Your Adapter
50	========================
51	
52	For more information on how to identify your adapter, go to the Adapter &
53	Driver ID Guide at:
54	
55	    http://support.intel.com/support/network/adapter/pro100/21397.htm
56	
57	For the latest Intel network drivers for Linux, refer to the following
58	website.  In the search field, enter your adapter name or type, or use the
59	networking link on the left to search for your adapter:
60	
61	    http://downloadfinder.intel.com/scripts-df/support_intel.asp
62	
63	
64	Command Line Parameters
65	=======================
66	
67	If the driver is built as a module, the  following optional parameters
68	are used by entering them on the command line with the modprobe command
69	using this syntax:
70	
71	     modprobe e1000 [<option>=<VAL1>,<VAL2>,...]
72	
73	For example, with two PRO/1000 PCI adapters, entering:
74	
75	     modprobe e1000 TxDescriptors=80,128
76	
77	loads the e1000 driver with 80 TX descriptors for the first adapter and
78	128 TX descriptors for the second adapter.
79	
80	The default value for each parameter is generally the recommended setting,
81	unless otherwise noted.
82	
83	NOTES:  For more information about the AutoNeg, Duplex, and Speed
84	        parameters, see the "Speed and Duplex Configuration" section in
85	        this document.
86	
87	        For more information about the InterruptThrottleRate,
88	        RxIntDelay, TxIntDelay, RxAbsIntDelay, and TxAbsIntDelay
89	        parameters, see the application note at:
90	        http://www.intel.com/design/network/applnots/ap450.htm
91	
92	        A descriptor describes a data buffer and attributes related to
93	        the data buffer.  This information is accessed by the hardware.
94	
95	
96	AutoNeg
97	-------
98	(Supported only on adapters with copper connections)
99	Valid Range:   0x01-0x0F, 0x20-0x2F
100	Default Value: 0x2F
101	
102	This parameter is a bit-mask that specifies the speed and duplex settings
103	advertised by the adapter.  When this parameter is used, the Speed and
104	Duplex parameters must not be specified.
105	
106	NOTE:  Refer to the Speed and Duplex section of this readme for more
107	       information on the AutoNeg parameter.
108	
109	
110	Duplex
111	------
112	(Supported only on adapters with copper connections)
113	Valid Range:   0-2 (0=auto-negotiate, 1=half, 2=full)
114	Default Value: 0
115	
116	This defines the direction in which data is allowed to flow.  Can be
117	either one or two-directional.  If both Duplex and the link partner are
118	set to auto-negotiate, the board auto-detects the correct duplex.  If the
119	link partner is forced (either full or half), Duplex defaults to half-
120	duplex.
121	
122	
123	FlowControl
124	-----------
125	Valid Range:   0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx)
126	Default Value: Reads flow control settings from the EEPROM
127	
128	This parameter controls the automatic generation(Tx) and response(Rx)
129	to Ethernet PAUSE frames.
130	
131	
132	InterruptThrottleRate
133	---------------------
134	(not supported on Intel(R) 82542, 82543 or 82544-based adapters)
135	Valid Range:   0,1,3,100-100000 (0=off, 1=dynamic, 3=dynamic conservative)
136	Default Value: 3
137	
138	The driver can limit the amount of interrupts per second that the adapter
139	will generate for incoming packets. It does this by writing a value to the 
140	adapter that is based on the maximum amount of interrupts that the adapter 
141	will generate per second.
142	
143	Setting InterruptThrottleRate to a value greater or equal to 100
144	will program the adapter to send out a maximum of that many interrupts
145	per second, even if more packets have come in. This reduces interrupt
146	load on the system and can lower CPU utilization under heavy load,
147	but will increase latency as packets are not processed as quickly.
148	
149	The default behaviour of the driver previously assumed a static 
150	InterruptThrottleRate value of 8000, providing a good fallback value for 
151	all traffic types,but lacking in small packet performance and latency. 
152	The hardware can handle many more small packets per second however, and 
153	for this reason an adaptive interrupt moderation algorithm was implemented.
154	
155	Since 7.3.x, the driver has two adaptive modes (setting 1 or 3) in which
156	it dynamically adjusts the InterruptThrottleRate value based on the traffic 
157	that it receives. After determining the type of incoming traffic in the last
158	timeframe, it will adjust the InterruptThrottleRate to an appropriate value 
159	for that traffic.
160	
161	The algorithm classifies the incoming traffic every interval into
162	classes.  Once the class is determined, the InterruptThrottleRate value is 
163	adjusted to suit that traffic type the best. There are three classes defined: 
164	"Bulk traffic", for large amounts of packets of normal size; "Low latency",
165	for small amounts of traffic and/or a significant percentage of small
166	packets; and "Lowest latency", for almost completely small packets or 
167	minimal traffic.
168	
169	In dynamic conservative mode, the InterruptThrottleRate value is set to 4000 
170	for traffic that falls in class "Bulk traffic". If traffic falls in the "Low 
171	latency" or "Lowest latency" class, the InterruptThrottleRate is increased 
172	stepwise to 20000. This default mode is suitable for most applications.
173	
174	For situations where low latency is vital such as cluster or
175	grid computing, the algorithm can reduce latency even more when
176	InterruptThrottleRate is set to mode 1. In this mode, which operates
177	the same as mode 3, the InterruptThrottleRate will be increased stepwise to 
178	70000 for traffic in class "Lowest latency".
179	
180	Setting InterruptThrottleRate to 0 turns off any interrupt moderation
181	and may improve small packet latency, but is generally not suitable
182	for bulk throughput traffic.
183	
184	NOTE:  InterruptThrottleRate takes precedence over the TxAbsIntDelay and
185	       RxAbsIntDelay parameters.  In other words, minimizing the receive
186	       and/or transmit absolute delays does not force the controller to
187	       generate more interrupts than what the Interrupt Throttle Rate
188	       allows.
189	
190	CAUTION:  If you are using the Intel(R) PRO/1000 CT Network Connection
191	          (controller 82547), setting InterruptThrottleRate to a value
192	          greater than 75,000, may hang (stop transmitting) adapters
193	          under certain network conditions.  If this occurs a NETDEV
194	          WATCHDOG message is logged in the system event log.  In
195	          addition, the controller is automatically reset, restoring
196	          the network connection.  To eliminate the potential for the
197	          hang, ensure that InterruptThrottleRate is set no greater
198	          than 75,000 and is not set to 0.
199	
200	NOTE:  When e1000 is loaded with default settings and multiple adapters
201	       are in use simultaneously, the CPU utilization may increase non-
202	       linearly.  In order to limit the CPU utilization without impacting
203	       the overall throughput, we recommend that you load the driver as
204	       follows:
205	
206	           modprobe e1000 InterruptThrottleRate=3000,3000,3000
207	
208	       This sets the InterruptThrottleRate to 3000 interrupts/sec for
209	       the first, second, and third instances of the driver.  The range
210	       of 2000 to 3000 interrupts per second works on a majority of
211	       systems and is a good starting point, but the optimal value will
212	       be platform-specific.  If CPU utilization is not a concern, use
213	       RX_POLLING (NAPI) and default driver settings.
214	
215	
216	
217	RxDescriptors
218	-------------
219	Valid Range:   80-256 for 82542 and 82543-based adapters
220	               80-4096 for all other supported adapters
221	Default Value: 256
222	
223	This value specifies the number of receive buffer descriptors allocated
224	by the driver.  Increasing this value allows the driver to buffer more
225	incoming packets, at the expense of increased system memory utilization.
226	
227	Each descriptor is 16 bytes.  A receive buffer is also allocated for each
228	descriptor and can be either 2048, 4096, 8192, or 16384 bytes, depending 
229	on the MTU setting. The maximum MTU size is 16110.
230	
231	NOTE:  MTU designates the frame size.  It only needs to be set for Jumbo 
232	       Frames.  Depending on the available system resources, the request 
233	       for a higher number of receive descriptors may be denied.  In this 
234	       case, use a lower number.
235	
236	
237	RxIntDelay
238	----------
239	Valid Range:   0-65535 (0=off)
240	Default Value: 0
241	
242	This value delays the generation of receive interrupts in units of 1.024
243	microseconds.  Receive interrupt reduction can improve CPU efficiency if
244	properly tuned for specific network traffic.  Increasing this value adds
245	extra latency to frame reception and can end up decreasing the throughput
246	of TCP traffic.  If the system is reporting dropped receives, this value
247	may be set too high, causing the driver to run out of available receive
248	descriptors.
249	
250	CAUTION:  When setting RxIntDelay to a value other than 0, adapters may
251	          hang (stop transmitting) under certain network conditions.  If
252	          this occurs a NETDEV WATCHDOG message is logged in the system
253	          event log.  In addition, the controller is automatically reset,
254	          restoring the network connection.  To eliminate the potential
255	          for the hang ensure that RxIntDelay is set to 0.
256	
257	
258	RxAbsIntDelay
259	-------------
260	(This parameter is supported only on 82540, 82545 and later adapters.)
261	Valid Range:   0-65535 (0=off)
262	Default Value: 128
263	
264	This value, in units of 1.024 microseconds, limits the delay in which a
265	receive interrupt is generated.  Useful only if RxIntDelay is non-zero,
266	this value ensures that an interrupt is generated after the initial
267	packet is received within the set amount of time.  Proper tuning,
268	along with RxIntDelay, may improve traffic throughput in specific network
269	conditions.
270	
271	
272	Speed
273	-----
274	(This parameter is supported only on adapters with copper connections.)
275	Valid Settings: 0, 10, 100, 1000
276	Default Value:  0 (auto-negotiate at all supported speeds)
277	
278	Speed forces the line speed to the specified value in megabits per second
279	(Mbps).  If this parameter is not specified or is set to 0 and the link
280	partner is set to auto-negotiate, the board will auto-detect the correct
281	speed.  Duplex should also be set when Speed is set to either 10 or 100.
282	
283	
284	TxDescriptors
285	-------------
286	Valid Range:   80-256 for 82542 and 82543-based adapters
287	               80-4096 for all other supported adapters
288	Default Value: 256
289	
290	This value is the number of transmit descriptors allocated by the driver.
291	Increasing this value allows the driver to queue more transmits.  Each
292	descriptor is 16 bytes.
293	
294	NOTE:  Depending on the available system resources, the request for a
295	       higher number of transmit descriptors may be denied.  In this case,
296	       use a lower number.
297	
298	
299	TxIntDelay
300	----------
301	Valid Range:   0-65535 (0=off)
302	Default Value: 64
303	
304	This value delays the generation of transmit interrupts in units of
305	1.024 microseconds.  Transmit interrupt reduction can improve CPU
306	efficiency if properly tuned for specific network traffic.  If the
307	system is reporting dropped transmits, this value may be set too high
308	causing the driver to run out of available transmit descriptors.
309	
310	
311	TxAbsIntDelay
312	-------------
313	(This parameter is supported only on 82540, 82545 and later adapters.)
314	Valid Range:   0-65535 (0=off)
315	Default Value: 64
316	
317	This value, in units of 1.024 microseconds, limits the delay in which a
318	transmit interrupt is generated.  Useful only if TxIntDelay is non-zero,
319	this value ensures that an interrupt is generated after the initial
320	packet is sent on the wire within the set amount of time.  Proper tuning,
321	along with TxIntDelay, may improve traffic throughput in specific
322	network conditions.
323	
324	XsumRX
325	------
326	(This parameter is NOT supported on the 82542-based adapter.)
327	Valid Range:   0-1
328	Default Value: 1
329	
330	A value of '1' indicates that the driver should enable IP checksum
331	offload for received packets (both UDP and TCP) to the adapter hardware.
332	
333	
334	Speed and Duplex Configuration
335	==============================
336	
337	Three keywords are used to control the speed and duplex configuration.
338	These keywords are Speed, Duplex, and AutoNeg.
339	
340	If the board uses a fiber interface, these keywords are ignored, and the
341	fiber interface board only links at 1000 Mbps full-duplex.
342	
343	For copper-based boards, the keywords interact as follows:
344	
345	  The default operation is auto-negotiate.  The board advertises all
346	  supported speed and duplex combinations, and it links at the highest
347	  common speed and duplex mode IF the link partner is set to auto-negotiate.
348	
349	  If Speed = 1000, limited auto-negotiation is enabled and only 1000 Mbps
350	  is advertised (The 1000BaseT spec requires auto-negotiation.)
351	
352	  If Speed = 10 or 100, then both Speed and Duplex should be set.  Auto-
353	  negotiation is disabled, and the AutoNeg parameter is ignored.  Partner
354	  SHOULD also be forced.
355	
356	The AutoNeg parameter is used when more control is required over the
357	auto-negotiation process.  It should be used when you wish to control which
358	speed and duplex combinations are advertised during the auto-negotiation
359	process.
360	
361	The parameter may be specified as either a decimal or hexadecimal value as
362	determined by the bitmap below.
363	
364	Bit position   7      6      5       4       3      2      1       0
365	Decimal Value  128    64     32      16      8      4      2       1
366	Hex value      80     40     20      10      8      4      2       1
367	Speed (Mbps)   N/A    N/A    1000    N/A     100    100    10      10
368	Duplex                       Full            Full   Half   Full    Half
369	
370	Some examples of using AutoNeg:
371	
372	  modprobe e1000 AutoNeg=0x01 (Restricts autonegotiation to 10 Half)
373	  modprobe e1000 AutoNeg=1 (Same as above)
374	  modprobe e1000 AutoNeg=0x02 (Restricts autonegotiation to 10 Full)
375	  modprobe e1000 AutoNeg=0x03 (Restricts autonegotiation to 10 Half or 10 Full)
376	  modprobe e1000 AutoNeg=0x04 (Restricts autonegotiation to 100 Half)
377	  modprobe e1000 AutoNeg=0x05 (Restricts autonegotiation to 10 Half or 100
378	  Half)
379	  modprobe e1000 AutoNeg=0x020 (Restricts autonegotiation to 1000 Full)
380	  modprobe e1000 AutoNeg=32 (Same as above)
381	
382	Note that when this parameter is used, Speed and Duplex must not be specified.
383	
384	If the link partner is forced to a specific speed and duplex, then this
385	parameter should not be used.  Instead, use the Speed and Duplex parameters
386	previously mentioned to force the adapter to the same speed and duplex.
387	
388	
389	Additional Configurations
390	=========================
391	
392	  Configuring the Driver on Different Distributions
393	  -------------------------------------------------
394	  Configuring a network driver to load properly when the system is started
395	  is distribution dependent.  Typically, the configuration process involves
396	  adding an alias line to /etc/modules.conf or /etc/modprobe.conf as well
397	  as editing other system startup scripts and/or configuration files.  Many
398	  popular Linux distributions ship with tools to make these changes for you.
399	  To learn the proper way to configure a network device for your system,
400	  refer to your distribution documentation.  If during this process you are
401	  asked for the driver or module name, the name for the Linux Base Driver
402	  for the Intel(R) PRO/1000 Family of Adapters is e1000.
403	
404	  As an example, if you install the e1000 driver for two PRO/1000 adapters
405	  (eth0 and eth1) and set the speed and duplex to 10full and 100half, add
406	  the following to modules.conf or or modprobe.conf:
407	
408	       alias eth0 e1000
409	       alias eth1 e1000
410	       options e1000 Speed=10,100 Duplex=2,1
411	
412	  Viewing Link Messages
413	  ---------------------
414	  Link messages will not be displayed to the console if the distribution is
415	  restricting system messages.  In order to see network driver link messages
416	  on your console, set dmesg to eight by entering the following:
417	
418	       dmesg -n 8
419	
420	  NOTE: This setting is not saved across reboots.
421	
422	  Jumbo Frames
423	  ------------
424	  Jumbo Frames support is enabled by changing the MTU to a value larger than
425	  the default of 1500.  Use the ifconfig command to increase the MTU size.
426	  For example:
427	
428	       ifconfig eth<x> mtu 9000 up
429	
430	  This setting is not saved across reboots.  It can be made permanent if
431	  you add:
432	
433	       MTU=9000
434	
435	   to the file /etc/sysconfig/network-scripts/ifcfg-eth<x>.  This example
436	   applies to the Red Hat distributions; other distributions may store this
437	   setting in a different location.
438	
439	  Notes:
440	
441	  - To enable Jumbo Frames, increase the MTU size on the interface beyond
442	    1500.
443	
444	  - The maximum MTU setting for Jumbo Frames is 16110.  This value coincides
445	    with the maximum Jumbo Frames size of 16128.
446	
447	  - Using Jumbo Frames at 10 or 100 Mbps may result in poor performance or
448	    loss of link.
449	
450	  - Some Intel gigabit adapters that support Jumbo Frames have a frame size
451	    limit of 9238 bytes, with a corresponding MTU size limit of 9216 bytes.
452	    The adapters with this limitation are based on the Intel(R) 82571EB,
453	    82572EI, 82573L and 80003ES2LAN controller.  These correspond to the
454	    following product names:
455	     Intel(R) PRO/1000 PT Server Adapter
456	     Intel(R) PRO/1000 PT Desktop Adapter
457	     Intel(R) PRO/1000 PT Network Connection
458	     Intel(R) PRO/1000 PT Dual Port Server Adapter
459	     Intel(R) PRO/1000 PT Dual Port Network Connection
460	     Intel(R) PRO/1000 PF Server Adapter
461	     Intel(R) PRO/1000 PF Network Connection
462	     Intel(R) PRO/1000 PF Dual Port Server Adapter
463	     Intel(R) PRO/1000 PB Server Connection
464	     Intel(R) PRO/1000 PL Network Connection
465	     Intel(R) PRO/1000 EB Network Connection with I/O Acceleration
466	     Intel(R) PRO/1000 EB Backplane Connection with I/O Acceleration
467	     Intel(R) PRO/1000 PT Quad Port Server Adapter
468	
469	  - Adapters based on the Intel(R) 82542 and 82573V/E controller do not
470	    support Jumbo Frames. These correspond to the following product names:
471	     Intel(R) PRO/1000 Gigabit Server Adapter
472	     Intel(R) PRO/1000 PM Network Connection
473	
474	  - The following adapters do not support Jumbo Frames:
475	     Intel(R) 82562V 10/100 Network Connection
476	     Intel(R) 82566DM Gigabit Network Connection
477	     Intel(R) 82566DC Gigabit Network Connection
478	     Intel(R) 82566MM Gigabit Network Connection
479	     Intel(R) 82566MC Gigabit Network Connection
480	     Intel(R) 82562GT 10/100 Network Connection
481	     Intel(R) 82562G 10/100 Network Connection
482	
483	
484	  Ethtool
485	  -------
486	  The driver utilizes the ethtool interface for driver configuration and
487	  diagnostics, as well as displaying statistical information.  Ethtool
488	  version 1.6 or later is required for this functionality.
489	
490	  The latest release of ethtool can be found from
491	  http://sourceforge.net/projects/gkernel.
492	
493	  NOTE: Ethtool 1.6 only supports a limited set of ethtool options.  Support
494	  for a more complete ethtool feature set can be enabled by upgrading
495	  ethtool to ethtool-1.8.1.
496	
497	  Enabling Wake on LAN* (WoL)
498	  ---------------------------
499	  WoL is configured through the Ethtool* utility.  Ethtool is included with
500	  all versions of Red Hat after Red Hat 7.2.  For other Linux distributions,
501	  download and install Ethtool from the following website:
502	  http://sourceforge.net/projects/gkernel.
503	
504	  For instructions on enabling WoL with Ethtool, refer to the website listed
505	  above.
506	
507	  WoL will be enabled on the system during the next shut down or reboot.
508	  For this driver version, in order to enable WoL, the e1000 driver must be
509	  loaded when shutting down or rebooting the system.
510	
511	  Wake On LAN is only supported on port A for the following devices:
512	  Intel(R) PRO/1000 PT Dual Port Network Connection
513	  Intel(R) PRO/1000 PT Dual Port Server Connection
514	  Intel(R) PRO/1000 PT Dual Port Server Adapter
515	  Intel(R) PRO/1000 PF Dual Port Server Adapter
516	  Intel(R) PRO/1000 PT Quad Port Server Adapter
517	
518	  NAPI
519	  ----
520	  NAPI (Rx polling mode) is enabled in the e1000 driver.
521	
522	  See www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI.
523	
524	
525	Known Issues
526	============
527	
528	Dropped Receive Packets on Half-duplex 10/100 Networks
529	------------------------------------------------------
530	If you have an Intel PCI Express adapter running at 10mbps or 100mbps, half-
531	duplex, you may observe occasional dropped receive packets.  There are no
532	workarounds for this problem in this network configuration.  The network must
533	be updated to operate in full-duplex, and/or 1000mbps only.
534	
535	Jumbo Frames System Requirement
536	-------------------------------
537	Memory allocation failures have been observed on Linux systems with 64 MB
538	of RAM or less that are running Jumbo Frames.  If you are using Jumbo
539	Frames, your system may require more than the advertised minimum
540	requirement of 64 MB of system memory.
541	
542	Performance Degradation with Jumbo Frames
543	-----------------------------------------
544	Degradation in throughput performance may be observed in some Jumbo frames
545	environments.  If this is observed, increasing the application's socket
546	buffer size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values
547	may help.  See the specific application manual and
548	/usr/src/linux*/Documentation/
549	networking/ip-sysctl.txt for more details.
550	
551	Jumbo Frames on Foundry BigIron 8000 switch
552	-------------------------------------------
553	There is a known issue using Jumbo frames when connected to a Foundry
554	BigIron 8000 switch.  This is a 3rd party limitation.  If you experience
555	loss of packets, lower the MTU size.
556	
557	Allocating Rx Buffers when Using Jumbo Frames 
558	---------------------------------------------
559	Allocating Rx buffers when using Jumbo Frames on 2.6.x kernels may fail if 
560	the available memory is heavily fragmented. This issue may be seen with PCI-X 
561	adapters or with packet split disabled. This can be reduced or eliminated 
562	by changing the amount of available memory for receive buffer allocation, by
563	increasing /proc/sys/vm/min_free_kbytes. 
564	
565	Multiple Interfaces on Same Ethernet Broadcast Network
566	------------------------------------------------------
567	Due to the default ARP behavior on Linux, it is not possible to have
568	one system on two IP networks in the same Ethernet broadcast domain
569	(non-partitioned switch) behave as expected.  All Ethernet interfaces
570	will respond to IP traffic for any IP address assigned to the system.
571	This results in unbalanced receive traffic.
572	
573	If you have multiple interfaces in a server, either turn on ARP
574	filtering by entering:
575	
576	    echo 1 > /proc/sys/net/ipv4/conf/all/arp_filter
577	(this only works if your kernel's version is higher than 2.4.5),
578	
579	NOTE: This setting is not saved across reboots.  The configuration
580	change can be made permanent by adding the line:
581	    net.ipv4.conf.all.arp_filter = 1
582	to the file /etc/sysctl.conf
583	
584	      or,
585	
586	install the interfaces in separate broadcast domains (either in
587	different switches or in a switch partitioned to VLANs).
588	
589	82541/82547 can't link or are slow to link with some link partners
590	-----------------------------------------------------------------
591	There is a known compatibility issue with 82541/82547 and some
592	low-end switches where the link will not be established, or will
593	be slow to establish.  In particular, these switches are known to
594	be incompatible with 82541/82547:
595	
596	    Planex FXG-08TE
597	    I-O Data ETG-SH8
598	
599	To workaround this issue, the driver can be compiled with an override
600	of the PHY's master/slave setting.  Forcing master or forcing slave
601	mode will improve time-to-link.
602	
603	    # make CFLAGS_EXTRA=-DE1000_MASTER_SLAVE=<n>
604	
605	Where <n> is:
606	
607	    0 = Hardware default
608	    1 = Master mode
609	    2 = Slave mode
610	    3 = Auto master/slave
611	
612	Disable rx flow control with ethtool
613	------------------------------------
614	In order to disable receive flow control using ethtool, you must turn
615	off auto-negotiation on the same command line.
616	
617	For example:
618	
619	   ethtool -A eth? autoneg off rx off
620	
621	Unplugging network cable while ethtool -p is running
622	----------------------------------------------------
623	In kernel versions 2.5.50 and later (including 2.6 kernel), unplugging
624	the network cable while ethtool -p is running will cause the system to
625	become unresponsive to keyboard commands, except for control-alt-delete.
626	Restarting the system appears to be the only remedy.
627	
628	
629	Support
630	=======
631	
632	For general information, go to the Intel support website at:
633	
634	    http://support.intel.com
635	
636	or the Intel Wired Networking project hosted by Sourceforge at:
637	
638	    http://sourceforge.net/projects/e1000
639	
640	If an issue is identified with the released source code on the supported
641	kernel with a supported adapter, email the specific information related
642	to the issue to e1000-devel[AT]lists.sf[DOT]net
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