We have a 4507 with redundant 4515 cards installed with a FIBER GBIC card in the uplink 1 slot in each card.
We recently had a power failure and since then our GBIC fiber connections are unable to link to our Fiber switch. I have replaced the GBIC cards with known good cards and did not link. I ran another known good fiber cable and did not get a link. I ran a fiber cable beween the GBIC cards in each 4515 and did get a link light between the cards. I did a controlled failure on the first 4515 and the second 4515 came active but no link to Fiber.
Not sure what to test next.
Tempted to power down 4500 and power back up but we are a TV station and would take us off the air.