Power outage, lost shadow, now it won't remount

[Victor Mendham]

Our site had a power outage and we lost our OpenVMS 5.5-2 cluster. When the power came on, one shadow disk would not come back, we get the error message

File Structure unrecognized.

The disks ese20 are off an HSC70 controller.

On all nodes in the cluster we can see them as online. They can be mounted as foreign, but no data shows up. They can not be mounted/system as the error File structure unrecognized is generated.

Any idea how to get them back, without doing an init and restore?

[Malcolm Wade]

Victor,

You don't say how long the power was off for so I'm assuming it must have been off for a fair while. ESE20's had a baby UPS and battery backup on board; enough to write the RAM data to an onboard hard drive in the event of a power failure.

It's been a while but weren't the ESE20's those original 120MB QBUS based solid state units; they were physically pretty big as I recall? In my time I saw someone turn them off the wrong way during a power failure and all the data was gone. I ALWAYS left the units to their own devices during power failures and they always came back correctly. Fiddling with the switches at the back was never a good idea; one switch actually isolated the UPS as I recall.

How many units were involved? You seem to indicate more than one which makes me think something was done incorrectly; either that or they're all got busted UPS or batteries or internal hard drives.

It sounds like the power outage was too long and the memory data just didn't get written to the backup disk; if that's the case I suspect you're gonna have to reload from tape.

Sorry,
Malcolm

[Victor Mendham]

Yes, power was off for way too long. I amazed someone else knew about these drives. You wouldn't happen to have a manual (pdf) or link for them would you. I also suspect that our h/w vendor, didn't look at these devices during our twice a year preventative maintenance schedule.

We are rebuilding one (out of 2), but the other we were keeping aside in the hopes of seeing if we can recover the data, just in case the restore isn't successful or the app has issues with the restored data.

Thanks.

[Malcolm Wade · Accepted solution]

Victor,

Sorry, it's been at least 7 years since my site dumped ours, about the time we migrated to StorageWorks bricks. I don't have any manuals lying around now.

Even a quick google search didn't produce a hit on ese20 manual either.

Anyone from HP out there have a manual? I recall the switch settings at the back were important BUT also recall there was big stickers on them re: what to turn on and off and the ramifications of doing the wrong one at the wrong time.

The good thing is, with 120MB they don't take long to restore! :-(

Regards.