At 09:35 AM 1/30/02, Patrick Donlon wrote: >Positive, if you look at the show port (on the other mail) you'll see there >are no collisions
This side is set (or auto-negotiated) to full duplex. Receiving while sending is not an error. This side should never report a collision. That doesn't mean that there can't be a duplex-mode mismatch. A mismatch could result in both sides reporting errors, just of different sorts. The other side could be set (or auto-negotiated) to half-duplex. You should check if it has errors, including collisions. If the half-duplex side does its normal CSMA/CD thing, senses no data, and happens to send while the other side is sending, the result is a collision from the half-duplex sender's viewpoint. The half-duplex side stops sending and backs off, in the middle of its frame. The result is probably a runt with either an alignment and/or Frame Check Sequence (FCS) error. The recipient receives an errored frame, even though it can't correlate this with a collision event. The recipient reports a runt and/or FCS or alignment error. Now, if you are sure that you don't have the obvious problem that everyone is going to assume you have (duplex mismatch), and you are still seeing alignment and FCS errors, then it's time to start investigating what else besides collisions could damage frames. An FCS means that the FCS placed in the frame by the sender doesn't match the FCS calculated by the recipient. In other words, a bit got changed. An alignment error means that the frame didn't end on an 8-bit boundary. In other words, a bit got dropped. Besides collisions, these errors could be caused by crosstalk, impedance mismatch, noise, running a power generator next the cables, lightning strikes, etc. Hope that makes sense. Please let us know the resolution. It will be a good learning experience. Priscilla >Thanks > > >""Steven A. Ridder"" wrote in message >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > Are you sure switch and NIC are the same speed and duplex? Looks like >port > > speed/duplex mismatch. > > ""Patrick Donlon"" wrote in message > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > Hi Everyone > > > > > > I trying to find some information on some Ethernet errors that I see on >a > > > port, see the text below. The machine is an RS6000 and was experiencing > > > some > > > performance problems, the NIC was set to auto negotiation and there >were > > > the > > > usual errors. The port and NIC are now both fixed and the errors are > > > increasing steadily, I've had a good search on the CCO but I can't find > > any > > > explanation of what causes the errors, any advice will be appreciated > > > > > > Regards > > > > > > Patrick ________________________ Priscilla Oppenheimer http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=33755&t=33687 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
