EMC DAE LCC path LEDs

Have a problem with a CX500 not seeing DAEs properly after power glitch. Shutting down the controllers, power cycling the DAEs and then starting the controllers again will probably resolve but can it be solved without downtime?

One back-end bus is happy. The other back end bus has green LEDs on the cable link LEDs but the loop ID LEDs are wrong. The left hand LCC has no LEDs lit on the path ID and the right hand LCC has LED1 flashing, this is the same on both DAEs on that back end bus.

Can this be resolved by  reseating an LCC or even a controller without upsetting the hosts and if so should it be the ones with the flashing path ID LED or the ones with no LED lit?

Also if there is a brownout for (let's say 1 second) do the controllers immediately get shut down by the SPS or will those hugely expensive batteries keep it running so it can reconnect to the DAEs when they power back on?
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andyalderAsked:
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Duncan MeyersCommented:
You can safely reseat the LCCS on the bad backend bus. The behaviour you're seeing is typical of duplicate enclosure IDs on the same bus. You may have a single LCC card that's failed and hanging the bus. Pull them one at a time to are if the issue resolves itself.

A 1 second brownout may be tolerated but f it's a full outage, then the 'hugely expensive batteries' aka SPS will sense a power outage and trigger a cache flush to vault. You'll then see the SPS run through a self test during which time write cache will be disabled. It should complete the self test within a few minutes so cache will be available without causing too much of a performance headache.
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andyalderAuthor Commented:
Couldn't work out which back end bus was the bad one so had to power-cycle the whole lot which sorted it out.
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