Cant get GB speed light on 4500

Question

Cant get GB speed light on 4500

olivermarshall (IS/IT--Management)

(OP)

27 Jan 09 09:56

Hi Chaps,

I have a 3COM 4500 here and I'm having problems getting any of the ports to work when set to GB speed. All the ports show as running at AUTO speed and when I query the port or the machine attached to it, they are all showing as running at 100mbps.

If I manually set the port at the workstation/server end to GB Full Auto then the network connection shows as being disconnected. This happens regardless of NIC hardware or OS; i've tried linux servers, windows servers and workstations and mac machines.

If I try setting any of the speed or connection settings for a port on the 4500 I get "the operation is not supported" in a popup window. This makes me think that something has been mis-set on the 4500 itself.

Anyone know what could be wrong that would stop me from be able to enable GB speeds on any port ?

Olly

FaiTHLeSS (TechnicalUser) · Answer 1 · 2009-01-27 10:08:49

Assuming you have brought the 4500G then it should run at gig speeds, are the devices plugged directly into the switch via a small patch cable?

Or are the cables going over structured cabling that are some distance away from the switch itself, could it be the cabling its causing the problem? If so have you tested just plugging one of the devices directly into the switch.

cknipe (MIS) · Answer 2 · 2009-01-27 16:10:25

How up to date is the firmware on the 4500. I would look into that also.

VinceWhirlwind (TechnicalUser) · Answer 3 · 2009-01-27 19:00:30

I've had the same thing when using "cat7" cabling, which was a customer's ridiculously expensive proprietary cabling and which was only 2-pair cable and so didn't work at Gb.

Bas1234 (TechnicalUser) · Answer 4 · 2009-01-28 17:45:11

@VinceWhirlwind, For Cat7 you have 4pair cables.

Does it work when you connect a Laptop/PC directly to the switch with a short patchcable?

___________________________________________
It works! Now if only I could remember what I did...
___________________________________________

VinceWhirlwind (TechnicalUser) · Answer 5 · 2009-01-29 01:51:56

New Postbas1234 (TechnicalUser)
28 Jan 09 17:45
@VinceWhirlwind, For Cat7 you have 4pair cables.

Not my customer's Cat7 - it was 2-pair, and so didn't work for 1Gb.

They were enormously pleased (not!) to learn they had to replace all their 2-pair patch leads with outrageously expensive 4-pair leads.

jdoebling (IS/IT--Management) · Answer 6 · 2009-03-27 19:46:51

cat 5e is rated to 1Gigbit. enough with the cabling! the big thing I see is that if you have a 4500 and not a 4500G, then you just dont have gig ports (except for the uplink ports). Is it a 4500 or a 4500G?

For example a 4500-26 port (non gig) is model 3CR17561-91, while the 4500G-24 port is model 3CR17761-91.

This is what you need to determine before you worry about anything else!

SYQUEST (TechnicalUser) · Answer 7 · 2009-03-28 13:46:36

That is what the "G" indicates in the model number.

....JIM....

Come Join Us!

Posting Guidelines

Cant get GB speed light on 4500