Chapter 10: Troubleshooting
3.
Ensure a proper LAN cable is being used
. Straight-through or crossover cabling is acceptable. The
LAN light of the gateway port to which any LAN is attached should be illuminated and green. If not,
ensure that the attached equipment is set for autonegotiation and can accept 100BaseTX Full-Duplex
links. Refer to front panel section of this document for other LAN light colors.
4. The network equipment attached to the LAN port of the gateway should be set for autonegotiation
mode in order to allow the gateway to negotiate a 100Mbit full-duplex connection. Forcing either the
gateway's or attached equipment's LAN port to 100Mbit full-duplex may not allow the proper
autonegotiation and LAN connection to occur. There are rare cases with older LAN equipment in
which it may be necessary to disable autonegotiation.
If CRC-errors or short packet errors are seen
in the management statistics of the LAN port, the attached LAN equipment has probably
configured itself to half-duplex mode and colliding packets are being lost
. In such a case,
autonegotiation should be disabled on
both
the gateway and the attached LAN equipment with both
forced to 100BaseTX full-duplex. Autonegotiation interoperability and standards were not well
understood by the industry at the inception of 100BaseTX, resulting in some older LAN equipment not
understanding the gateway's autonegotiation advertisement of strictly full-duplex capability.
5. Monitor lights during packet transmission:
•
With LANs attached, verify, perhaps using pings, that data packets generated by a local machine
cause the gateway's light of the connected LAN port to blink. If not, determine if there is an
intermediate router or piece of equipment that is not properly forwarding the data packets to the
gateway. Examine the Link/Activity light on the source machine and any intermediate machines to
ensure they behave properly (usually flicker) as well.
6. Enlist the aid of a sniffer program to view at the source and destination machines exactly what data
packets are being sent and received. Free public-domain programs such as Wireshark are readily
available.
Chapter 11: Third Party Copyright Notices
E3Switch is grateful for and contributes to open source software development which may be protected by
the following copyright notices and license terms:
eCos License
E3Switch gratefully acknowledges the contributions of the eCos developers and community. Current eCos source files are available at
http://ecos.sourceware.org/
E3Switch
implementation-specific modifications to those files are available by contacting E3Switch LLC.
The FreeBSD Copyright
Copyright 1994-2006 The FreeBSD Project. All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials
provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE FREEBSD PROJECT ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FREEBSD
PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
The views and conclusions contained in the software and documentation are those of the authors and should not be interpreted as representing official policies, either expressed or
implied, of the FreeBSD Project.
The Net-SNMP Copyright
---- Part 1: CMU/UCD copyright notice: (BSD like) -----
Copyright 1989, 1991, 1992 by Carnegie Mellon University
Derivative Work - 1996, 1998-2000
Copyright 1996, 1998-2000 The Regents of the University of California
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