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Catalyst 3750X , Switching ..need help


I\ve got stuck in problem with cisco 3750x switches..

I have 2 3750x switches, with fiber module GLC-GE-100FX in C3KX-NM-1G.

both have tha same, and both are totally new.

now i have to connect these two via fiber optic cable...but HOW???

i cant assign ip address any can i connect these two...?

and other thing, each switch will get traffic through its gigethernet ports(24P), and then send traffic to other switch via fiber, the other switch recieve from fiber, and send through gigabit it all will work???

cant understand...

the network is class b  private address range..

kindly reply me back with the solutions..preferably without vlans....


2 Replies 2

Rising star
Rising star


Since this is your 1st post ill just say welcome here (not that i am an ambassador for anything ) it just sounds nicer to welcome people 

Well first of all the 3750x supports the modules so there seems to be no problem there.

However due to the nature of the question i would recomend that you contact a cisco certified partner and hire a technichian to do the work for you. This is the absolutely best advice i can give you!

IF you want to do the work yourself anyway and i do not recomend this, then we are looking at the bare minimum config and that is as i can understand the following.

do the following on both of your switches.

without power install the network module into the switch (it is hotswap so it should not be bothered if the switch is on or not, but the recomendation is that it is installed without power to minimice risks)

Install the sfp into the slot you just installed

install the fiber cabeling (DO NOT LOOK INTO THE FIBERS EVER ! ) this is a big thing ! NEVER look into a fiber directly, if its the wrong one you might loose your eyesight or damage it.

boot both switches

hope that the lights light up

if they do not then switch the cables in one of the ends (if the send and recieve have been crossed)

if they both light up and you have contact between them then its all alright with the configuration inbetween them and the switch will do what the switch does best, ie switch packets from one interface to another.

now it is all up to what you put into them

if this does not work then we are back to sol.ution 1, Call your local cisco engineer and have them come down and do it the correct way for your network.

Good luck


Thankyou very much HTH for compliments and for the answer.

with your answer , i have accomplished first stage...the LEDs changed to Green now..

Actually ii'm not the new one with 3750.. I'm CCNP , and have done configuration on 3750, in labs...

but never used the fiber cable,,just used, now facing some problem while configuring fiber..thats why asking you the whole..

as , now you knew the whole scenario, can you guide me, in which way i can accomplish this..

3 3750X  switches should connect via fiber to the 4th one.. and multiple nodes connctiong to the 3 switches via gigabit ethernet.

and need output via gigabitethet from the single switch.....

can you, or someone guide....

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