If the link light for the port does not come on, you can consider these possibilities: Connect cable from switch to a known good device. Make sure that both ends of the cable are plugged into the correct ports. I have an issue with some EX2300 series images where the optical ports allow trafic, but the led stay. When it works, the network does reach high transfer speed beyond 1GbE, but there are constant disconnections, and the internet connection is very slow. I have an extreme switch recently configured, the optical port is not working very good. The cable can have encountered physical stress that causes it to be functional at a marginal level. The fiber between closets is fairly new. The trap logs look like. The NAS operates as expected for several days, maintaining a 10GbE connection. However, after a period of time (3-5 days), it unexpectedly droping connection to 5Gbe, affecting my workflow and data transfer rates.
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