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GBIC Stack Configuration

I have just purchased 2 2950G Switches using 2 gbic modules. Do I need to connect both cable to the corresponding port.

IE

Switch 1, GBIC 1, Port 1 into Switch 2, GBIC 2, Port 1

And likewise with the second port ?

If so could you tell me why there are 2 green lights for port 1 to 1 and port 2 to 2 is showing a green and amber light.

Hope this makes sense ?

1 ACCEPTED SOLUTION

Accepted Solutions

Re: GBIC Stack Configuration

Hi,

there are two ports on stacking GBIC to enable daisy-chaining.

So if you want just to connect two switches, connect port 1 to 1 and that's all - you have 2 Gbps connection (full duplex). If you connect port 1 to 1 and port 2 to 2 (as you described) one port is blocked by STP (amber light) to prevent a loop.

But you can also stack three (and more) switches. If you connect port 1 on switch1 to port 1 on switch2 and port2 on switch 2 to port 1 on switch3, you are having three switches daisy-chained. But the speed degrades to 1Gbps in this case (half-duplex).

Regards,

Milan

1 REPLY

Re: GBIC Stack Configuration

Hi,

there are two ports on stacking GBIC to enable daisy-chaining.

So if you want just to connect two switches, connect port 1 to 1 and that's all - you have 2 Gbps connection (full duplex). If you connect port 1 to 1 and port 2 to 2 (as you described) one port is blocked by STP (amber light) to prevent a loop.

But you can also stack three (and more) switches. If you connect port 1 on switch1 to port 1 on switch2 and port2 on switch 2 to port 1 on switch3, you are having three switches daisy-chained. But the speed degrades to 1Gbps in this case (half-duplex).

Regards,

Milan

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