I have a Cisco 9200L-48P-4X switch connected to a Cisco 3850-24X switch via 10Gb SFP modules. The modules are LRM which I am using mode conditioning patch cables on both ends to condition the light for about 120ft of OM1 fiber. I am using two of these 10Gb links in a port channel, one is working fine, not a single flap but the other has gone down and back up a few times which the port goes into err-disabled status due to the flapping. Today I replaced the LRM module on one end to see if there are any changes and will do the same on the other end if it happens again. I also the first time it happened, changed to a different pair of fibers on the bulkhead. I have checked the interface summary on both sides and there are no errors on the ports or anything that would indicate issues with the fiber run or SFP modules.
I am just curious if anyone could provide some advice as to how I could investigate this issue a little bit more? I find it odd for the link to just flat out be lost and then come right back a few times unless maybe one side the light coming from the LRM is going off?
Any advice would be greatly appreciated, thank you.
