QSFP-40G-SR-BD BiDi optics not detected on Nexus N9K-C93180YC-FX while QSFP-40GE-LR4 works
3
On a Cisco Nexus N9K-C93180YC-FX, QSFP-40G-SR-BD BiDi modules are not detected at all: nothing appears in the logs when they are inserted and they are absent from 'show interface transceiver', whereas QSFP-40GE-LR4 modules in the same ports are logged and listed normally. Several QSFP-40G-SR-BD units were tried, including a newly purchased one. The Cisco compatibility matrix lists the optic as supported on this switch from NX-OS 7.0(3)I7(1); the poster tested both 7.0(3)I7(1) and 7.0(3)I7(3) without success and attached screenshots of the transceiver and module outputs.
- Hardware: Cisco Nexus N9K-C93180YC-FX
- Transceivers: QSFP-40G-SR-BD, QSFP-40GE-LR4
- Form factor: QSFP+
Symptoms / messages:
QSFP-40G-SR-BD not detected
no syslog message on module insertion
module missing from show interface transceiver
QSFP-40GE-LR4 works in the same ports
Comments 4
A respondent asked for the insertion logs and the port's show output, and another noted that the working QSFP-40GE-LR4 is a single-mode optic while QSFP-40G-SR-BD needs multimode OM3 or better fiber, asking the poster to clarify the cabling.
A respondent recommended three steps: confirm the QSFP-40G-SR-BD is Cisco-branded, since Cisco does not test or support third-party optics and ruling them out is the first troubleshooting step; upgrade NX-OS to the recommended 9.3(7)/9.3(7a); and upgrade the switch's EPLD/FPGA images to match, because the MI FPGA talks to transceivers over I2C and can cause detection failures or bad SPROM reads.
Another respondent said that an optic that is detected but does not link should get a hard-coded speed with negotiation disabled, while an optic that is not detected at all is probably third-party; they reported a run of 40G optic and DAC problems with a vendor whose name begins with F and ends in 'ore' (i.e., Fiberstore/FS.com).
A respondent reported that an ACI upgrade broke a batch of brand-new third-party optics on this same switch model and they had to be replaced with Cisco optics; they also endorsed moving to the 9.x long-term release. No resolution was confirmed by the poster.