Using the SFP-10G-SR with the WS-C2960X-24PD-L on "Te1/0/1" interface

[JJBGage]

Hi,

As the title indicates.  I have a 2960X switch that has two SFP+ interfaces.  From everything I've read the SFP-10G-SR module should work in these 10 gig SFP+ interface.

However, I get zero activity when I try to use these SFP-10G-SR module.  Here are some additional specs: 

Switch Ports Model SW Version SW Image
------ ----- ----- ---------- ----------
* 1 30 WS-C2960X-24PD-L 15.2(7)E9 C2960X-UNIVERSALK9-M

NAME: "1", DESCR: "WS-C2960X-24PD-L"
PID: WS-C2960X-24PD-L , VID: V07 , SN: FJC2307W2DL

NAME: "TenGigabitEthernet1/0/1", DESCR: "SFP-10GBase-SR"
PID: SFP-10G-SR , VID: V03 , SN: ECL170800Q7

NAME: "TenGigabitEthernet1/0/2", DESCR: "SFP-10GBase-SR"
PID: SFP-10G-SR , VID: V03 , SN: ECL170300ZU

Thank you

[JJBGage]

Hmmmm.  Ok, thanks again.  I will give it a shot.

[JJBGage]

Hi,

Sorry for the delayed response.  I was out of the country since 22 Apr.  Anyway, I purchased the "SFP-10G-SR-S" and tried it and had no success.  Do you have any other suggestions?  Please see below:

CAT2960x24-1#show inve
CAT2960x24-1#show inventory
NAME: "1", DESCR: "WS-C2960X-24PD-L"
PID: WS-C2960X-24PD-L , VID: V07 

NAME: "TenGigabitEthernet1/0/1", DESCR: "SFP-10GBase-SR"
PID: SFP-10G-SR-S , VID: V01 , SN: AVD2339D6DP

Thanks again.

[Leo Laohoo]

Please post the complete output to the following commands: 

sh post
sh idprom interace Ten1/0/1
sh interface Ten 1/0/1 trans details

Copy-n-paste the above output into a text file and attach to the next reply.

[JJBGage]

Leo,

Per your request please see attached file.

Thank you!

[Leo Laohoo]

The optic looks like it is faulty. 

Ok, let's try this simple test:  Loop the port of the optic and see if the link light lights up (green or amber).  

Basically, connect a LC strand into one port and connect the other end to the other port forming a "loop".  If the port goes up (green) or amber (error-disable), the optic is good.  If it remains dark then it only proves the optic is faulty.

[JJBGage]

Leo,

If "optic" you're referring to the SFP module, then the "SFP-10G-SR-S" doesn't work/light up.  I tried the module in a different 2960X and the SFP-10G-SR-S doesn't appear to work in either 2960X.  

[Leo Laohoo]

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@JJBGage wrote:
If "optic" you're referring to the SFP module, then the "SFP-10G-SR-S" doesn't work/light up.  I tried the module in a different 2960X and the SFP-10G-SR-S doesn't appear to work in either 2960X.  

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Ok, so the next move is to RMA the SFP-10G-SR with Cisco because it is Cisco-branded. 

INFO: 

There are people out there (including Cisco staff) who claim that one cannot just simply RMA any Cisco-branded optic if said optic is not covered under some kind of Maintenance Contract or SmartNet.  That information is NOT TRUE because I have been routinely RMA all of our Cisco-branded SFP+ and QSFP for many years and I've just recently RMAed two SFP+ on 07 May 2025.  

When I raised the RMA request on 07 May 2025, Cisco Logistics did question me about the absence of a maintenance contract against the optic and I reminded them that maintenance contract on optics are not mandatory but, rather, optional.  RMA of optics falls under the same "category" (or basket) as RMAing of a power supply, network module, fan assembly, etc.  However, when asked I provided Cisco Logistics several serial numbers of our Catalyst 9300 switches (all without any maintenance contract either) before Cisco Logistics allowed my case to proceed and my replacement optics will arrive by the end of this week.  

I also reviewed the serial number of the suspected faulty optic, AVD2339D6DP.  The age of the optic is less than 6 years old (important) and is still able to be RMAed.

[JJBGage]

Interesting and very good to know info.  Thank you for that.  

In the meantime, I cracked the seal on another two (purchased 10) and tried the loop test with these two.  They went from blinking amber to immediately blinking green.  I then tried them on a 4507 switch and they remained dark.  They also remained dark on the 2960X (unless they were looped).

[Leo Laohoo]

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@JJBGage wrote:

Interesting and very good to know info.  Thank you for that.  

In the meantime, I cracked the seal on another two (purchased 10) and tried the loop test with these two.  They went from blinking amber to immediately blinking green.  I then tried them on a 4507 switch and they remained dark.  They also remained dark on the 2960X (unless they were looped).

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NOTE:  I am not talking about the new optics. 

I think the fibre plant could be faulty ... or the fibre plant is single-mode.  

Do the same loopback test with the fibre plant and see if the link lights light up or not.

[JJBGage]

Leo,

I'm running OM3 (aqua colored) fiber.  The runs are at or less than 250 yards. They are all connected directly on the switches uplinks using either SFP-10G-SR (4507/4948) or GLC-SX-MMD (2960X/3850).  In other words, the 2960X are connected to the 3850(both are using GLC-SX-MMD).  The 3850 are connected to the 4507 ( here the 3850 is using GLC-SX-MMD and the 4507 is using SFP-10G-SR).  The 4948 is directly connected to the 4507 (both are using SFP-10G-SR).  So all this suggests multimode fiber plant across the network.

Please let me know your thoughts.  Thanks.

[Leo Laohoo]

Is there a FOBOT in between the local and remote optics?  Or is this a direct run?

Ok, so do a loopback test over the fibre plant and see if the link lights up.

[JJBGage]

It's a direct run. 

Leo, I'm a little out of my depth here.  Are you asking me to perform a loopback test across an entire run of a network leg or on the same switch?  I used the attached devise and got the SFP to blink yellow/green.

[Leo Laohoo]

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@JJBGage wrote:
Are you asking me to perform a loopback test across an entire run of a network leg or on the same switch?

---

Ok, let's assume there is a 2960X directly connected to a 4500X.  The optics are not lighting up.  

Connect the fibre, from the 2960X, directly to the 4500X.  Except, this time, unplug the 4500X and perform the same loopback test.  (This exercise is a poor-man's method to do a visible fault light test on the fibre run itself.  This test will include the optic from the 2960X and the fibre run.)  If the optic at the 2960X works, then do the same exercise the opposite direction (this will test the fibre run and the optic at the 4500X.)

Hope this makes sense.

[JJBGage]

OK, I will perform test once I return home on Friday.

[JJBGage]

Leo,

Sorry for the delay.  Well I got it to work.  Let me know if you want me to send you results of any particular tests.  

Thank you again for your help.