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<TITLE>RE: Weird networking issue.</TITLE>
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<P><FONT SIZE=2>By nature, a hub is half-duplex - it's a repeater.</FONT>
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<P><FONT SIZE=2>Besides, misconfigured duplex will not cause CRC errors.</FONT>
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<P><FONT SIZE=2>C.</FONT>
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<P><FONT SIZE=2>-----Original Message-----</FONT>
<BR><FONT SIZE=2>From: David G. Andersen [<A HREF="mailto:dga@lcs.mit.edu">mailto:dga@lcs.mit.edu</A>]</FONT>
<BR><FONT SIZE=2>Sent: Tuesday, January 07, 2003 2:08 PM</FONT>
<BR><FONT SIZE=2>To: Drew Weaver</FONT>
<BR><FONT SIZE=2>Cc: 'nanog@merit.edu'</FONT>
<BR><FONT SIZE=2>Subject: Re: Weird networking issue.</FONT>
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<P><FONT SIZE=2>Rule number 1 with any ethernet: Check to make sure you have the duplex</FONT>
<BR><FONT SIZE=2>and rate statically configured, and configured identically on both ends of</FONT>
<BR><FONT SIZE=2>the connection.</FONT>
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<P><FONT SIZE=2>I'd wager you've got half duplex set on one side, and full on the other...</FONT>
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<P><FONT SIZE=2> -Dave</FONT>
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<P><FONT SIZE=2>On Tue, Jan 07, 2003 at 02:19:10PM -0500, Drew Weaver mooed:</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> Hi, this is kind of a newbie question but this doesn't make a whole lot of</FONT>
<BR><FONT SIZE=2>> sense :P</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> I have an etherstack hub connected to a FastEthernet port on a cisco 3660</FONT>
<BR><FONT SIZE=2>> router, these are the stats when I do a show int fast0/0:</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> 5776 input errors, 5776 CRC, 2717 frame, 0 overrun, 0 ignored</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> Whats weird is I just cleared the counters 12 minutes ago, and already there</FONT>
<BR><FONT SIZE=2>> are almost 6000 CRC errors. This connected via a standard Cat5 ethernet</FONT>
<BR><FONT SIZE=2>> cable, I have tried replacing the cable to noavail.</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> Is this a fairly normal situation, If so that's great, but it seemed rather</FONT>
<BR><FONT SIZE=2>> ridiculous to me, and if it is not a normal situation, what would cause</FONT>
<BR><FONT SIZE=2>> this?</FONT>
<BR><FONT SIZE=2>> </FONT>
<BR><FONT SIZE=2>> Any ideas are appreciated.</FONT>
<BR><FONT SIZE=2>> Thanks,</FONT>
<BR><FONT SIZE=2>> -Drew Weaver</FONT>
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<P><FONT SIZE=2>-- </FONT>
<BR><FONT SIZE=2>work: dga@lcs.mit.edu me: dga@pobox.com</FONT>
<BR><FONT SIZE=2> MIT Laboratory for Computer Science <A HREF="http://www.angio.net/" TARGET="_blank">http://www.angio.net/</A></FONT>
<BR><FONT SIZE=2> I do not accept unsolicited commercial email. Do not spam me.</FONT>
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