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New Member

port Led doesn't light after connection


I have a old catalyst 3500XL, In the aim to upgrade my lan i have bought a C 3750, but i have a problem when i try connect the 3750 on my lan.

My lan :

Intranet ---- 3500XL ==== 4908 ---- internet

on the 3500XL, there is a gbic LX

My futur lan :

intranet ----- 3750 ==== 4908 ---- internet

On the 3750 there is a gbic sfp LX

When i try to connect the 3750 the port led doesn't light, and i haven't got log on the 3750 :/

On the 4908, there are ACL rules.

If you want i can give you config files.

Thank you in advance for your answer.

Ps: sorry for my English, I'm a french student


Re: port Led doesn't light after connection

is the 3750's interface actually go up/up but LED is not lighting up? If it's up/up with no LED, is it actually passing traffic? ping test fo connectivity. If you answer yes to all of this, then the LED is probably not fuctioning and that's all it is. You can send it back to your vendor and get one with working LED.

New Member

Re: port Led doesn't light after connection

To bosalaza :

When I connect on the same port an other 3750 with a gbic sfp SX the port led lighting up ( So the led works ).

There are no passing traffic and no log ( to show the connection and disconnection on this port ).

The 3750s, the gbic sfp LX and the optical fiber is new... !

The optical fiber (ST/LC) of the 3750 has the same specification 9/125 monomode that the optical fiber of the 3500 (SC/ST).

If i'm right, the Gbic Lx of the 3500 works with 1300-nm wavelength and the Gbic sfp Lx of the 3750 too.

So I really don't see where is the problem ( hardware ? software ? ).

Thank you Slash


Re: port Led doesn't light after connection

Try pressing the Status button on the very left side of the switch. The button changes what information the LED displays. You may be currently displaying something other than Link status, such as PoE.

Please rate all helpful posts.


New Member

Re: port Led doesn't light after connection

Oki thank you,

I will try and I will rate your post :)

New Member

Re: port Led doesn't light after connection

All seems ok .... :/ No amber....

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