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reconfigure port to become Combo-Fiber??


We have a SF 300-48P 48-Port 10/100 PoE Managed Switch.

How do I reconfigure one of its GBIC-enabled ports to be a Combo-Fiber port so it properly sees and uses a single-mode or multi-mode fiber GBIC??

The admin manual says ComboF is one of the options for Port Type, but our switches do not enable its configuration??

Please clarify??

Thank you, Tom

4 Replies 4

Kevin Tomomitsu

Hi Tom,

     I am currently working on a SF 300-24P with an 802.1Q trunk link to a SF 302-8P using the GBIC interfaces with single-mode SFP's. Based on my configuration and the manual the port should automatically recognize the SFP and switch the port type to ComboF instead of ComboC. The ports are setup to Autonegotiate 10/100/1000 Full Duplex. Hope this helps.

Your comments make sense but no red/laser light is visible inside the GBIC after it's inserted and the port settings etc. don't recognize the presence of a GBIC in the port.

I also discovered today that I have the wrong kind of GBIC -- single-mode instead of multi-mode -- but still the internal light should be active once the GBIC is inserted, when I look into our HP GBICs I can see a tiny red laser light dot and I don't see one within the sfp-300's GBIC after it's inserted...this is with trying two separate/different GBICs in the GBIC ports.

Thank you, Tom

Hi Tom,

     What I found was that instead of setting the ports to autonegotiate I had to lock it down on both side to 1000 Full Duplex. I will check with Cisco TAC on this since on the old SRW224G4P (Linksys) switch the speed and duplex did not have to be manually set for this to work. We are using Cisco SFP-GE-L single-mode Fiber SFP's. I will need to double check if these SFP's are supported on this switch model, we just tried to mimic what we had setup originally with our older switches. Hope this helps.


I will try this tomorrow and see if the lights go on inside the GBIC etc. or if this has any effect.

I can't really do anything till next Monday and I'm waiting to know if I can exchange the GBICs, if I can't I must leave the original HP switches in place JUST for the GBICs -- IF I can do this with the current switch/stacking configuration etc.

Thank you, Tom

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