is Cisco SFP GLC-LH-SMD compatible with Arista SFP SFP1G-LX-31?

[Herman2018]

Hi ,good day, we encounter one issue with our peer who is using Arista switch/ router with SFP SFP1G-LX-31. Our side SFP is GLC-LH-SMD, the switch is C93180YC-FX. the error message is UDLD Tx-Rx Loop. Is the issue related to the SFP compatible? Please help advise, thanks in advance.

[Leo Laohoo]

UDLD does not necessarily point to a faulty optic.  

Have the cable path been tested with a reputable OTDR?

[Herman2018]

thanks @Leo Laohoo for your prompt advice. We haven't carried out OTDR yet. So most probably it is fiber cable path issue, right? thanks again.

[Leo Laohoo]

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@Herman2018 wrote:
So most probably it is fiber cable path issue, right? thanks again.

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No, that's not what I said nor meant. 

Incorrectly replacing optics is more expensive than getting someone to do a proper OTDR.

[Herman2018]

Thanks Leo. my question is about Cisco SFP compatibility with other brand SFP. Hope you or someone can advise. 

[Leo Laohoo · Accepted solution]

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@Herman2018 wrote:
my question is about Cisco SFP compatibility with other brand SFP.

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Cisco-branded optics can "talk" to other brand of optics as long as they are in the same wavelength and speed.

[Herman2018]

Thanks @Leo Laohoo  so much for your advice.