SG100-24 miniGBIC uplink port doesn't work

[khuongnguyen017]

I've just purchased 2 switches SG100-24 and use fiber cable to connect these switch together. I plugged cable in module MGBSX1 and then put it into miniGBIC uplink port but despite trying many times, also rebooted devices, I still not make these uplink ports up. Could you please help to advice me how can I bring them up?

Thank you very much.

Best regards,

Khuong Nguyen.

[nguyenha_uit]

I also have same problem. Does anyone help to advise?

Thanks.

[David Hornstein]

Hi Mr Nguyen,

Thank you very much for the very clear photographs.

The Quick start guide that comes with the unit , which i have referenced below and attached says on page 6;

• MiniGBIC interface is a combination port, shared with one other RJ-45 interface. When the MiniGBIC is active, the closest RJ-45 port is

disabled.

reference:

http://www.cisco.com/en/US/docs/switches/lan/csbus/sf10x-xx_sg10x-xx/quick_start/guide/78-19225-01.pdf

Sorry for this inconvenience.

Regards Dave

[khuongnguyen017]

Hi Dave,

Thanks for your answer. But actually, I cannot active miniGBIC port. MiniGBIC still no signal even if I unplugged RJ45 cable at the closest port and plug fiber into miniGBIC. Do you know how can I active them?

Thanks.

Regards,

Khuong.

[David Hornstein]

Hi Khuong.

Ah please excuse my old eyes, your pictures tell a thousand words.

In the picture, you have a yellow patch cable going to the MGBSX1. 

Yellow cable denotes single mode (SM) fiber patch cable with a 9um fiber core..This is not the correct cable for a MGBSX1, which uses Multimode fiber cable.

The MGBSX1 is a 1000SX standard  Small Form factor Pluggable (SFP),  requiring a MultiMode (MM) patch cable..

Multimode cables usually have, if you look closely, 62.5um or 50um written on the cable to denote the fiber core thickness.

So,  you should have a Multimode patch cable between the existing  miniGBICs and not a yellow single mode cable (9um).

If you look closely at the existing patch cable and on it you see  9um on the cable, you are using the wrong cable to connect the switches together,.

So your options are;

• replace the MGBSX1 (MM SFP) at both ends of the fiber run  with MGBLX1 (SM SFP)  or
• replace the Single mode  fiber run with MultiMode fiber cable. 

This second option depends on the length of the MM fiber used, fiber core size  and the quality of the MM cable used..

the chart below will most likely help you;

Product	Wavelength (nm)	Fiber Type	Core Size (μm)	Modal Bandwidth (MHz* Km)***	Operating Distance (meters)
1000BASE-SX	850	MMF	62.5	160 (FDDI-grade)	220 (722 ft)
			62.5	200 (OM1)	275 (902 ft)
			50	400	500 (1,640 ft)
			50	500 (OM2)	550 (1,804 ft)

regards Dave

[khuongnguyen017]

Thanks Dave so much. Sorry for this basic error. I will replace the cable and revert back to you soon.

Regards,

Khuong.