Richard, Jim, Dave:

at 12:05 the h1seib2 (BS) front end system went offline. We saw no green leds on the IO Chassis One Stop card, and saw red leds on the card itself. We power cycled h1seib2 and its IO Chassis (we prevented the models from running). The computer could not see any cards in the chassis.

We powered down both h1seib2 (BS) and h1seib3 (ITMX) systems, and switched the One Stop fibers at the IO Chassis (h1seib2 connected to h1seib3's chassis and vice versa). Confusingly now both FE computers can see all the cards in both chassis. We then powered everything back down and connected the fibers back correctly. At this point the problem has gone away,  h1seib2 sees its cards again. We started the user models, the only problem was with h1iopseib3 which had a run-away IRIG-B time with went up to 1500 and took an hour to come back down.

Richard says that the One Stop card in the h1seib2 IO Chassis showed a red led when the computer was not powered up, but the h1seib3 chassis did not do this. So we are still suspicious of the h1seib2's IO Chassis One Stop card, and if this problem re-appears we will consider replacing it.

An interesting aside, I looked at the IO Chassis One Stop cards in the CER and found that while most have 4 green leds on, some have 1 and one has 2.