Things to check if the SFP/SFP+ link is not coming up. Ensure that a compatible transceiver is used. This document describes how to troubleshoot fiber optic interfaces by addressing some of the fiber optic module and cabling specifications. The information in this document is based on all Catalyst 9000 Series switches. So has anyone an idea why the SFP connections / interfaces are acting so weirdly? Or do I miss anything? I am sitting on that issue since two days now, searching the. In most cases, SFP-related faults are not caused by the module itself but by factors such as fiber contamination, incorrect cable polarity, incompatible optics, or configuration mismatches. Depending on the type of connector in the patch panel, (ST, SC, FC, or LC) the user will need to separate the cable and it may get swapped. Scope FortiSwitch and FortiGate.
[PDF Version]