Problem with SFP on the different types swithes

[stranger1971]

Hi.

I need to connect several switches. They are 2 2960CX, 2 4500E, 2 SG500X.

All the SFPs are Intel FTLX1471DJBCV-i3. The optical media is SMF.

The 4500E recognized the SFP as 10G-LR.

The SG500X recognized the SFP as 1000BASE-LX.

The 2960CX recognized the SFP as 1000BASE-LH.

4500s work fine together on 10G speed.

2960s work fine together on 1G speed.

SG500s work fine together on 1G speed.

All of them don't work with any other type switch.

What is wrong? How to troubleshoot the problem?

Thanks for any ideas.

[Seb Rupik]

Hi there,

The fact that all the switches identify the SFP as a different module should be grounds for not using it all!

I suggest you use compatible SFP modules in your switches, which will be Cisco own brand. If in doubt check:

https://tmgmatrix.cisco.com/

cheers,

Seb.

[Giuseppe Larosa]

Hello stranger1971,

what you are describing is  possible, because Intel has introduced dual rate optics see link below

Usually regardless how the SFP is seen on the switches, the SFP optics either works at 10 G EXOR works ar 1 Gbps.

The explanation is that at OSI layer1 physical layer 10 G on fiber uses different line code and other techniques compared to 1 Gbps. The small format factor does not allow space to have dual devices in a single SFP, but Intel was able to do this.

Read the following links from wikipedia

https://en.wikipedia.org/wiki/10_Gigabit_Ethernet

and

https://en.wikipedia.org/wiki/Gigabit_Ethernet

Follow Sep's suggestion and change SFPs. In addition to Cisco branded SFPs also optics of other vendors can work like Finisar.

Edit:

Intel declares to have dual rate 10G / 1G SFPs so what you have seen is possible.

see

https://www.intel.com/content/www/us/en/support/articles/000005528/network-and-i-o/ethernet-products.html

However, I am afraid you cannot use them with Cisco switches as Cisco switches expect to see either an SFP+ 10G or an SFP 1G. There is no way for a Cisco switch to choice the speed of an optics.

Intel declares their SFP+ dual rate are compatible with the following products:

Intel® Ethernet Converged Network Adapter X520-DA2

Intel® Ethernet Converged Network Adapter X520-LR1

Intel® Ethernet Converged Network Adapter X520-SR1

Intel® Ethernet Converged Network Adapter X520-SR2

Hope to help

Giuseppe

[Seb Rupik]

If you follow @Giuseppe Larosa suggestion of using non-cisco SFPs it may be prudent to use the following commands to ensure the switchports are not stuck in an err-disable state:

!
service unsupported-transceiver
no errdisable detect cause gbic-invalid
!

cheers,

Seb.

[stranger1971]

Ok. I'll try the second command.
First one is enable now.

[stranger1971]

Very good links.
Thanks you!