Multi-mode SFPs with SMF, link-light. Multi-mode SFPs with MMF, no link-light.

New remote site, we thought there was MMF in place from the DMARC to MDF, but turns out it was SMF. We ordered MM SFPs for the DMARC side (Ciena) and MM SFPs for the MDF side (Meraki SW). Tech onsite connected the fiber (1 long 220ft LC-LC fiber jumper) we got link light, but our throughput was only 10mbps. Turns out it was SMF connecting DMARC to MDF. Order a new LC-LC 220ft fiber jumper but made sure it was MMF. Ran the fiber, connected both ends, no link-light. Tried swapping the cable ends (think ciena was just passthrough), no luck. Tried swappign SFPs, no luck.

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Here's the notes I have two simply diagrams I made.

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--DMARC--

Ciena 3903x

(To MDF) SFP Port2: Ciena SFP (XCVR-B00G85)

(From Street) SFP Port3: Ciena SFP (XCVR-A10Y31)

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--MDF--

Meraki MS120-24p

SFP Port25: Meraki SFP (MA-SFP-1GB-SX)

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Link-light - https://i.imgur.com/IBr6wDV.png
No Link-light - https://i.imgur.com/N5wIl6P.png