Switch Killed Computer's LAN port

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

I connected a Asound 8 port switching hub to my network and one of the
computers suddenly could no longer communicate over the LAN. It couldn't get
an IP address. I verified that this is not a software problem by swapping
the hard drive and OS from an identical computer. I installed another LAN
cards in this computer and it now work fine with the same cable, etc. The
problem port is an on-board port on a Biostar M7NCG motherboard. I've reset
the CMOS, but that didn't help. The problem port's lights come one when the
cable is plugged in, but it will not acquire an IP address. It also will not
communicate when I set a static IP address. The NIC appears fine in Device
Manager. The port has been working fine for the last three months right up
until I installed the switching hub. It appears the switch caused the
problem. However, other computers connected to the switch were not affected
and the switch appears to be working fine. I've installed a LAN card in the
problem computer and all is well, but this has me wondering.

What could cause this problem? Is it possible that the switch is defective
and it sent out an electrical current that damaged the port? I'm concerned
that the switch could cause more problems. Is there a way to test a switch's
LAN port to check its electrical characteristics?

Thank you,
Steve Smith

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

Steve Smith wrote:

> What could cause this problem? Is it possible that the switch is defective
> and it sent out an electrical current that damaged the port? I'm concerned
> that the switch could cause more problems. Is there a way to test a
> switch's LAN port to check its electrical characteristics?

Two quick tests.

Does that computer work in other switch ports?
Does that port work with other computers?

It's unlikely that any device damaged another. The voltage required to do
that, simple does not exist on the NICs and they're also connected to the
line via transformers, so there's no direct connection, between devices.

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

James Knott wrote:
> Two quick tests.
> Does that computer work in other switch ports?
> Does that port work with other computers?...

No, the computer's problem port does not work in other switch ports or when
connected directly to the router.
Other computers and other LAN cards in this computer work just fine on the
same cable and switch port.

The problem is definately with the computer's onboard LAN port. Perhaps it
was just a coincidence that the port died when I connected it to the new
switch. Any other ideas?

Thanks,
Steve Smith

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

Steve Smith wrote:

> The problem is definately with the computer's onboard LAN port. Perhaps it
> was just a coincidence that the port died when I connected it to the new
> switch. Any other ideas?

What do the lights on the NIC show? What does the operating system show for
status?

 

[Guest]

Archived from groups: comp.dcom.lans.ethernet (More info?)

In article <YY6dnX6TLYA-RtLfRVn-sw@rogers.com>,
james.knott@rogers.com says...
> Steve Smith wrote:
>
> > What could cause this problem? Is it possible that the switch is defective
> > and it sent out an electrical current that damaged the port? I'm concerned
> > that the switch could cause more problems. Is there a way to test a
> > switch's LAN port to check its electrical characteristics?
>
> Two quick tests.
>
> Does that computer work in other switch ports?
> Does that port work with other computers?
>
> It's unlikely that any device damaged another. The voltage required to do
> that, simple does not exist on the NICs and they're also connected to the
> line via transformers, so there's no direct connection, between devices.

I had a lightning strike about a year ago, hopped on the network, and
over half the ports on a 24+2 switch got zapped. In many cases, the
downstream NICs got zapped as well. In a couple cases the NIC got
zapped, but the port on the switch was still ok, and vice versa. So,
it's possible, but perhaps much less so under normal circumstances.




--
Randy Howard (2reply remove FOOBAR)
"Making it hard to do stupid things often makes it hard
to do smart ones too." -- Andrew Koenig