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New Member

CAT5E patch cables and Cisco switches

I am having an issue with Cisco 3524 switches and CAT5E or enhanced patch cables. I show connectivity lights but cannot pass data. ( Obtain an IP address).

I know the fix ( use different patch cables) any idea why?

Thanks in advance.


Re: CAT5E patch cables and Cisco switches

Let me ask some stupid questions:

1) Are you sure the patch cables are good? Have you tried them anywhere else? Have you put them on a wire tester?

2) Are you're 5e patch cables booted where your regular CAT V ones might not be? Sometimes booted cables are hard to get to seat properly in the switch ports.

3) Are you sure they are straight through and not cross-over? (the 5e's that is) I've made that mistake once.

4)Are you sure that switching the cables *does* fix your problem?

All that being said, there is no reason that the 5e would preform differently than regular old cat 5. It's still going to pass data according to the switch port speed setting regardless of whether or not the patch cord is rated to go faster than 10/100. I have quite a number of Catalyst 35xx switches in my network with 5e patch cords plugged in, and I have never seen that problem. Check the cords, and check to see if they're seated correctly.

New Member

Re: CAT5E patch cables and Cisco switches

do you get any errors on the inteface ? If you configure static IP address, does your PC work.

the above link shows you the correct cabling for this product

New Member

Re: CAT5E patch cables and Cisco switches

Is it on boot that you fail to obtain an IP address? If so, have you checked the spanning tree settings on the switch. If they are default (spanning tree enabled) then it is very likely that the port is still learning while the PC is trying to DHCP an address. If this is the case use portfast on PC ports to rectify.

New Member

Re: CAT5E patch cables and Cisco switches

I have a similar situation, kind of....We went from old type 1 cable to Cat5e at our one facility. We unplugged our pc's from the old wiring and plugged them into the new wiring. Sometimes they worked and sometimes they did not. This was using 2924XLs running 12.0(5) XU with portfast enabled. The only way we were able to get the ports to come back was to power off the switch.

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