Optical Link Fail with CPAK-100G-LR4 and QSFP-100G-ER4L-S

[lsunny]

Hi All,

I am having an issue with two transceivers.

I am trying to establish a 100G fiber link between ASR-9000 and Catalyst 9500-32C.

I used CPAK-100G-LR4 and QSFP-100G-ER4L-S but the link is not coming up. I even used Attenuator. But still fails.

Anybody has similar experience?

[marce1000]

  - Make sure that for both devices compatible SFP's are used ; check with https://tmgmatrix.cisco.com/
     + Checkout https://www.optcore.net/show-interface-transceiver-details/?srsltid=AfmBOorEXvikTBKYE8k2GMSHFpPfR31BI2LGFLSwaMOLxttCTM4PBD5l#h-show-transceiver-details-on-cisco-switches

   - Use latest advisory software version for both  ASR-9000 and Catalyst 9500-32C , especially if one of the boxes is running an older release currently , 

 M.

[Leo Laohoo]

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@lsunny wrote:
I used CPAK-100G-LR4 and QSFP-100G-ER4L-S

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That's the wrong wavelengths. 

CPAG-100G-LR4 wavelengths are:  1295, 1300, 1304, 1309

QSFP-100G-ER4L-S wavelength is:  1310.

[lsunny]

But Cisco Data sheets says below,

Cisco QSFP-100G-ER4L-S

The Cisco QSFP100 ER4-Lite supports link lengths of up to 40km over a standard pair of G.652 single-mode fiber with duplex LC connectors. The 100 Gigabit Ethernet signal is carried over four wavelengths. Multiplexing and demultiplexing of the four wavelengths are managed within the device. Full 40km reach requires the use of FEC on the host platform. Without FEC, the reach is 30km. The QSFP100 ER4-Lite provides backward compatibility with Cisco’s CPAK ER4-Lite, whose reach is up to 25km, and with IEEE 100GBASE-ER4 standardized transceivers, such as Cisco’s CFP 100G ER4, up to 30km. It also interoperates with Cisco’s QSFP100 and CPAK IEEE 100GBASE-LR4 modules up to 10km.

I believe both transceivers are operating four different wavelengths and doing WDM. Correct me If am wrong.

[Leo Laohoo]

@Marvin Rhoads, what say you?

[Marvin Rhoads]

The data sheets and Cisco Optics Product Information pages seems to have some conflicting information regarding these optics. While the data sheets says they are interoperable (https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/datasheet-c78-736282.html), the COPI page shows them operating at different wavelengths. (https://copi.cisco.com/?tpid=6&tpid=33)

I suggest you open a TAC case to resolve the issue. They may have additional non-public information to aid you in finding a resolution of the issue.

[Leo Laohoo]

Do what @Marvin Rhoads says and raise a TAC Case.  

I am keen to say what TAC has to say.  

I could be mistaken but I do not believe a link between an ER and an LR would work because they are different wavelengths and frequencies.  

[Carl Lindahl]

Do you have a valid TX and RX power at either side? both the 9500 and ASR9000? If your QSFPs don't have a valid RX power but are both TX, there is a physical problem. IF there is RX power on both sides, but link is not coming up, have you checked FEC, etc?