[27205] in resnet
Re: Ethernet ports "burning out"
daemon@ATHENA.MIT.EDU (Peter Allmaker)
Wed Jan 25 21:34:32 2012
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Date: Wed, 25 Jan 2012 21:34:13 -0500
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From: Peter Allmaker <Peter.Allmaker@MCLA.EDU>
To: RESNET-L@listserv.nd.edu
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Could you have your electrician check outlets for bad ground? Maybe you hav=
e more than data flowing through the wire. Was the cheap switch plugged int=
o a different outlet? What is up on the room side in terms of extension cor=
ds, etc.?
Good luck,
p
On Jan 25, 2012, at 9:19 PM, Resnet Forum <RESNET-L@LISTSERV.ND.EDU> wrote:
> I would put a cheap Linksys switch in the students' room, so that your
> expensive switch can't be affected.
>=20
> Frank
>=20
> -----Original Message-----
> From: Resnet Forum [mailto:RESNET-L@LISTSERV.ND.EDU] On Behalf Of Brad
> Coburn
> Sent: Wednesday, January 25, 2012 8:08 PM
> To: RESNET-L@LISTSERV.ND.EDU
> Subject: Ethernet ports "burning out"
>=20
> Hi all.
>=20
> I have a curious situation that perhaps the community might be able to
> offer some insight on. I apologize for the length of my post; I hope the
> detail will serve to spark some insight.
>=20
> Some background:
> Two, 10-story residence halls. One Ethernet port per student (so
> 2-person rooms have two Ethernet ports). Three equipment rooms per hall,
> serving approximately 1/3 of each building. 15, 48-port 10/100 switches
> total in each building.
>=20
> The situation:
> Suddenly this Fall I have a recurring issue with a single student room.
>=20
> The initial report is that they cannot establish connection with their
> laptops. One is a PC, one is a MAC; neither looks terribly old (I'm on
> the network side, not the desktop side).
>=20
> First time, troubleshooting turns up "bad" Ethernet ports on that switch
> for these two connections. Not an uncommon occurrence across residence
> halls. If it's important, the two patch cords are adjacent (jacks were
> patched in, in-order).
>=20
> Moved patch cords to two spare ports (happen to be adjacent) on that
> switch; service restored (confirmed with my tester and customer machines).=
>=20
> Two weeks later (second time), call comes back. No link. Troubleshooting
> shows two "bad" Ethernet ports again. There are only three of us who
> work on switches in the field, and nothing's been touched (so the patch
> cables are where they were). Moved both patch cords to another switch,
> adjacent ports, same model.
>=20
> Some days later (third time), call comes back. It's "bad" ports again.
> So I and my tech go out there. Standard tests come back fine.
> Re-terminated the jack "just in case". I brought my cable pair tester to
> try advanced functions like TDR, as well as resistance and voltage
> measurements pair-to-pair and pair-to-ground, with computers connected
> and without computers connected. Nothing comes up.
>=20
> By now I'm out of sufficient spare ports, so I place these two
> connections on a little desktop Netgear switch and patch that into the
> stack. This is just before Thanksgiving break. Student connections again
> confirmed working with tester and customer computers.
>=20
> Shortly thereafter we replace the two switches with "bad" ports (there
> had been other port failures over the years) with two new switches from
> spare stock. One switch is the same model. One switch is the newest
> model of the 10/100 class - a model I'm placing in other buildings that
> won't support or can't afford GigE.
>=20
> The Netgear setup worked the whole time, but it's a non-standard setup
> and will only come back to haunt us later. So we pulled the Netgear out
> and placed the room patch cords back in their usual spot, which is now
> also on the new replacement switch.
>=20
> Everything worked fine from approximately post-Thanksgiving Break until
> last Thursday, January 19. Most students returned from Winter Break on
> Tuesday January 24.
>=20
> Call is back (fourth time). Ports are "bad" again, on this brand-new
> switch. This model supports extended diagnostics, which sometimes report
> bad ports. Nothing comes up this time (this is not atypical).
>=20
> Tech and I followed the cable in the ceiling all the way to the IDF
> (only one floor down). This room is roughly in the middle of the cable
> runs, and the room next door shares a common route from the hallway.
> Inspection turned up nothing in the way of obvious damage. Moved the
> customer patch cords to two spare ports on the new switch.
>=20
> So tomorrow I have Facilities scheduled to go up and run new cable for
> this room. The parents are irate at this point.
>=20
> I'm more than sure that this is a customer equipment issue, but I can't
> figure out what could be happening. We've not seen anything like this
> before. A single-port occurrence would be more likely rather than a
> simultaneous 2-port event.
>=20
> It may be important to know that when the campus was originally cabled
> someone took advantage of the "economy" offered by 10Mbps Ethernet's
> operation over 2-pair. So we split the cable at the faceplate and then
> again back in the IDF. That's how it was done back then, and we're still
> operating successfully at 100Mbps now (but we stopped the practice for
> retro-fits some time ago).
>=20
> Given our "split" architecture in this case, I suppose there's a remote
> possibility that a damaging event on one half of the cable could
> transfer to the entire cable. It's also just as likely that if customer
> equipment damages the first connection, the customer tries the second
> connection immediately and blows that too.
>=20
> I certainly understand what this looks like for the customer, but I
> don't know what else to say. Of course the customers aren't doing
> anything out of the ordinary, and neither is anyone else they might
> invite into the room.
>=20
> I have not tried:
> - Swapping horizontal cables with the neighbor. If the problem follows,
> then it's ours. It's too late now though; Facilities will replace this
> cable and we will pull the old one down to more thoroughly inspect for
> physical damage.
> - Separating the two patch cords for the room between switches. It just
> hasn't happened.
> - Installing a surge suppressor on the line (I have pricing).
>=20
> I really would like to know what I can do to damage an Ethernet port. By
> the way, my tester "sees" the bad ports as a switch connected, but
> powered off. Which should mean that it sees the transformer at the front
> of the interface. In no case has the tester reported any "error"
> condition. Oh, and it's a Fluke LinkRunnerPRO.
>=20
> Any thoughts?
>=20
> Thanks.
>=20
> -Brad Coburn
> Associate Director, Communications Technologies
> Information Technology
> The College of New Jersey
>=20
>=20
> 15 switches
> 48 ports each
>=20
> ___________________________________________________
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>=20
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> go to http://LISTSERV.ND.EDU/archives/resnet-l.html
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>=20
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<html><head></head><body bgcolor="#FFFFFF"><div>Could you have your electrician check outlets for bad ground? Maybe you have more than data flowing through the wire. Was the cheap switch plugged into a different outlet? What is up on the room side in terms of extension cords, etc.?</div><div><br></div><div>Good luck,</div><div>p<br><br></div><div><br>On Jan 25, 2012, at 9:19 PM, Resnet Forum <<a href="mailto:RESNET-L@LISTSERV.ND.EDU">RESNET-L@LISTSERV.ND.EDU</a>> wrote:<br><br></div><div></div><blockquote type="cite"><div><!--?xml version="1.0" encoding="ISO-8859-1"?-->
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<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">I would put a cheap Linksys switch in the students' room, so that your</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">expensive switch can't be affected.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Frank</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">-----Original Message-----</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">From: Resnet Forum [<a href="mailto:RESNET-L@LISTSERV.ND.EDU" target="_blank">mailto:RESNET-L@LISTSERV.ND.EDU</a>] On Behalf Of Brad</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Coburn</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Sent: Wednesday, January 25, 2012 8:08 PM</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">To: <a href="mailto:RESNET-L@LISTSERV.ND.EDU">RESNET-L@LISTSERV.ND.EDU</a></font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Subject: Ethernet ports "burning out"</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Hi all.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">I have a curious situation that perhaps the community might be able to </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">offer some insight on. I apologize for the length of my post; I hope the </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">detail will serve to spark some insight.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Some background:</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Two, 10-story residence halls. One Ethernet port per student (so </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">2-person rooms have two Ethernet ports). Three equipment rooms per hall, </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">serving approximately 1/3 of each building. 15, 48-port 10/100 switches </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">total in each building.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">The situation:</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Suddenly this Fall I have a recurring issue with a single student room.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">The initial report is that they cannot establish connection with their </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">laptops. One is a PC, one is a MAC; neither looks terribly old (I'm on </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">the network side, not the desktop side).</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">First time, troubleshooting turns up "bad" Ethernet ports on that switch </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">for these two connections. Not an uncommon occurrence across residence </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">halls. If it's important, the two patch cords are adjacent (jacks were </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">patched in, in-order).</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Moved patch cords to two spare ports (happen to be adjacent) on that </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">switch; service restored (confirmed with my tester and customer machines).</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Two weeks later (second time), call comes back. No link. Troubleshooting </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">shows two "bad" Ethernet ports again. There are only three of us who </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">work on switches in the field, and nothing's been touched (so the patch </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">cables are where they were). Moved both patch cords to another switch, </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">adjacent ports, same model.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Some days later (third time), call comes back. It's "bad" ports again. </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">So I and my tech go out there. Standard tests come back fine. </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Re-terminated the jack "just in case". I brought my cable pair tester to </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">try advanced functions like TDR, as well as resistance and voltage </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">measurements pair-to-pair and pair-to-ground, with computers connected </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">and without computers connected. Nothing comes up.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">By now I'm out of sufficient spare ports, so I place these two </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">connections on a little desktop Netgear switch and patch that into the </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">stack. This is just before Thanksgiving break. Student connections again </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">confirmed working with tester and customer computers.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Shortly thereafter we replace the two switches with "bad" ports (there </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">had been other port failures over the years) with two new switches from </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">spare stock. One switch is the same model. One switch is the newest </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">model of the 10/100 class - a model I'm placing in other buildings that </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">won't support or can't afford GigE.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">The Netgear setup worked the whole time, but it's a non-standard setup </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">and will only come back to haunt us later. So we pulled the Netgear out </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">and placed the room patch cords back in their usual spot, which is now </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">also on the new replacement switch.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Everything worked fine from approximately post-Thanksgiving Break until </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">last Thursday, January 19. Most students returned from Winter Break on </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Tuesday January 24.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Call is back (fourth time). Ports are "bad" again, on this brand-new </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">switch. This model supports extended diagnostics, which sometimes report </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">bad ports. Nothing comes up this time (this is not atypical).</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Tech and I followed the cable in the ceiling all the way to the IDF </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">(only one floor down). This room is roughly in the middle of the cable </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">runs, and the room next door shares a common route from the hallway. </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Inspection turned up nothing in the way of obvious damage. Moved the </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">customer patch cords to two spare ports on the new switch.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">So tomorrow I have Facilities scheduled to go up and run new cable for </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">this room. The parents are irate at this point.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">I'm more than sure that this is a customer equipment issue, but I can't </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">figure out what could be happening. We've not seen anything like this </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">before. A single-port occurrence would be more likely rather than a </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">simultaneous 2-port event.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">It may be important to know that when the campus was originally cabled </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">someone took advantage of the "economy" offered by 10Mbps Ethernet's </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">operation over 2-pair. So we split the cable at the faceplate and then </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">again back in the IDF. That's how it was done back then, and we're still </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">operating successfully at 100Mbps now (but we stopped the practice for </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">retro-fits some time ago).</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Given our "split" architecture in this case, I suppose there's a remote </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">possibility that a damaging event on one half of the cable could </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">transfer to the entire cable. It's also just as likely that if customer </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">equipment damages the first connection, the customer tries the second </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">connection immediately and blows that too.</font></div>
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<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">I certainly understand what this looks like for the customer, but I </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">don't know what else to say. Of course the customers aren't doing </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">anything out of the ordinary, and neither is anyone else they might </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">invite into the room.</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">I have not tried:</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">- Swapping horizontal cables with the neighbor. If the problem follows, </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">then it's ours. It's too late now though; Facilities will replace this </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">cable and we will pull the old one down to more thoroughly inspect for </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">physical damage.</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">- Separating the two patch cords for the room between switches. It just </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">hasn't happened.</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">- Installing a surge suppressor on the line (I have pricing).</font></div>
<br>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">I really would like to know what I can do to damage an Ethernet port. By </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">the way, my tester "sees" the bad ports as a switch connected, but </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">powered off. Which should mean that it sees the transformer at the front </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">of the interface. In no case has the tester reported any "error" </font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">condition. Oh, and it's a Fluke LinkRunnerPRO.</font></div>
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<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Any thoughts?</font></div>
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<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Thanks.</font></div>
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<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">-Brad Coburn</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Associate Director, Communications Technologies</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">Information Technology</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">The College of New Jersey</font></div>
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<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">15 switches</font></div>
<div align="left" style="text-align:left;"><font face="Geneva" size="-1" color="#000000" style="font-family:Geneva;font-size:9pt;color:#000000;">48 ports each</font></div>
<br>
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