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New Member

3750G-48TS and GLC-LH-SM

Anyone had any issues with getting a GLC-LH-SM module to work in a 3750G-48TS switch? Any special commands to make it work?

I have a customer who can't see any link lights not see the 2960G switch on the other end with another GLC-LH-SM module. I've tried the "speed nonegotiate" command but no luck.


Re: 3750G-48TS and GLC-LH-SM

Since GLC-LH-SM is supported (HW)on both devices, lets check if IOS does:

Also, if you do show int where those modules are connected, do you see any description for the media type, that will let us know if GLC modules are being detected or not.

New Member

Hi all,Client installed a

Hi all,

Client installed a single mode fibre run from Distribution Switch to Access switch. The distance is not even greater than 100 Metres but the client insisted since the fibre is free.

on the Cisco Catalyst 2960X-24TS-L (Access layer not stacked) the switch is identified, but on the Cisco Catalyst 2960X-24TS-L (Distribution switch stacked) the sfp module is "unknown".

Gi1/0/49 access_sw po notconnect 1 auto auto 1000BaseLX SFP

Gi1/0/49 dist_sw po notconnect 1 auto auto unknown

Distribution switch is running 150-2.EX4
Access switch is running 150-2.EX5

I have configured on both sides
speed nonegotiate, above output is showing that the 2 are not even talking to each other since their status is still auto auto...

Any ideas is gladly appreciated!

New Member

Re: 3750G-48TS and GLC-LH-SM

Nevermind. Shame on me for believing the customer. Turns out the TX and RX strands were reversed on one end. . . . . .

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