Intermittent connection loss

[JimJx]

Hi folks,

I have a problem that I hope someone can point me to a solution to.....

I have a 3500 XL with approximately 25 workstations connected. The way the boxes are connected is pretty standard, the cable goes from workstation to a network jack, CAT5 to the punch panel, then a patch cable from there to the switch.

Out of the 25 users, I have 2 that are problematic. They will intermittently lose connection. All boxes are running W2K Pro, and from time to time they get a message that the network cable is unplugged. This can last for a couple seconds to a few minutes.

I have pulled new cat5, changed ports on the switch, new patch panel (that was NOT what I consider fun), new NICs, and in one case a new box, and the problem persists....

The25 users are on the same floor in the building, but in different wings. They use the same IDF, the offices are about 100 ft apart and these are the only two that are having any problems. The total length of CAT5 is 100 - 150 ft. I can't find any similarities, other than losing the connections.

I was thinking EMI, but I can't find it if it is there and if that is the problem, why only these two boxes? I was also thinking about going from UTP to STP to see if that helped.....

Anyone have any ideas before I pull out the rest of my hair?

Thanks in advance,
Jim

 

[vipergg]

Are you seeing any kind of errors on these links ? CRC"S runts etc... Are they autonegotiating ? If you haven't tried yet , hardcode both sides to 100/full or whatever speed you want them to run . May be you can parse thru this link and get an idea what may be happening .

http://www.cisco.com/en/US/partner/...s700/products_tech_note09186a00800a7af0.shtml

 

[JimJx]

My apologies for taking so long to reply to you. I did as you suggested and set the ports to 100 instead of auto negotiate. Haven't had them drop since.

Thank you very much for the help Viper.

Jim