Content Unrecognized Issue

[deystad]

Hi

 

I have a Lacie AIT-2 DAT Drive (Sony SDX-520C mechanism) run on a Mac OS 10.3.9 and Retrospect 5.0.238. It connects via Firewire or USB. All issues have been duplicated using both connections.

 

Problem started with tapes coming up as erased (the daily backup tape as well as a couple older tapes we tried to retrieve data from). We sent the drive in to be repaired.

 

When we got it back all efforts to either retrieve data, verify data or rebuild backup sets result in a "content unrecognized" message. I believe all 13 or 14 tapes have been tested in someway and all get the "content unrecognized" message.

 

The drive was sent back to repair place (Techware, Minneapolis) and returned to me a couple weeks later. Still has same problem.

 

To further confuse the issue, I took a brand new tape, created a new backup set, backed up some data to it and retrieved it, no problem.

 

I've spent several hours troubleshooting including looking at many similar issues on this forum. It doesn't seem like it could be a problem with drive unless for some reason it can't read the BOT stuff. BTW, all tapes were created on this drive. It is the only DAT drive like this we've ever owned.

 

Any ideas? Thank you very much.

 

Dick

[rhwalker]

To further confuse the issue, I took a brand new tape, created a new backup set, backed up some data to it and retrieved it, no problem.

Did you perform this same test when the drive was in its initial failure mode before sending it for repair for the first time? That would be a valuable piece of information.

 

Simply FYI, because of failures like this, and also to prevent grave disorder from typing the wrong thing during a panic restore, I always write protect tapes when they go into storage. The write protect mechanism is designed to override hardware instructions to write to / erase the tape (at least that was how it was done years back when I used to write device drivers, etc.).

 

Here are some thoughts.

 

When the drive was sent for repair, perhaps the drive's guts were swapped out or the heads aligned. That could end up giving you a drive with different alignment. If the original drive was out of alignment, the current "same drive" might not be able to read the old tapes. Unlikely, because the standard has a lot of slop in it, but I just toss this out.

 

If new tapes can be written and read, you know that the current mechanism works.

 

Consider the possibility that the failure mode was that the erase head was always turned on. That would erase any tape put into the drive. Have you tried the same experiment (reading old tapes) using a tape that was never put into the drive while it was in the failure mode?

 

Are you sure that the tapes were made with this version of Retrospect? On this same computer?

 

Have you tried updating to Retrospect 5.1.177 (and updating the RDU)? I think that was a free update from 5.0. Files are here:

Retrospect 5.1 updates

 

Consider the possibility that the drive previously had "hardware compression" checked and now has it disabled. That would make the tape unreadable. Or encryption. Check Retrospect's preferences - perhaps you changed something.

 

That's about the best I can suggest. Sounds to me like those tapes are, in fact, unreadable. I will take your word for it that they were made with Retrospect. Retrospect is expecting to see its headers.

 

Russ

[deystad]

Russ,

 

Thank you very much for replying.

 

No, I didn't try creating a new data set and tape before sending for repair. I researched the "Erased" problem on the forums and most pointed to the drive needing repair/cleaning, so I sent it in.

 

This has been going on for 3-4 months so not positive, but pretty sure I didn't try every data set/tape before repair. Even if some of the tapes were actually erased, not all of them should have been. I have tried every data set/tape including some that I'm pretty sure were not put in during original Erased issue.

 

According to the CSR I've talked to, they didn't swap the guts, but who knows. I thought of the issue you're talking about, but do not have another drive to test it. The CSR did say he would try to verify or recover a data set using a similar drive of theirs. I may take him up on this, if only to get something for the $300 I spent.

 

All tapes were made using version 5.0 of Retrospect. I have tried the computer tapes were made on as well as another.

 

I tried updating to Retrospect 5.1.177 but it would not take my serial number. My Retrospect 5.0 is an OEM version that came with drive. Even so, I would have thought it would be able to update to 5.1. I don't know what the RDU is. Is it drive firmware? Maybe I'll do a post on just the update issue to find out.

 

The tapes were all created with hardware compression turned on, but not encryption. I can't find any reference in preferences to turning on a "Read Data is Compressed" sort of preference. So if there is something like that, it could definitely be an issue. It seems a proprietary application like this would determine if the data its trying to read is compressed or not and then deal with it accordingly.

 

Any final thoughts by anybody would be appreciated.

 

Thanks, again.

 

Dick

[rhwalker]

Also check the possibility that the original failure mode was breaking the tapes. We once had a drive that went into such a failure mode. Use care when you get two tapes in a row that aren't readable because the drive might be in a mode that is destroying your backup archives.

 

Russ

[rhwalker]

I don't know what the RDU is.

It's the Retrospect Driver Update, and the version should print in the log at each launch, along with Retrospect's version. It won't load if you don't have a compatible version. See:

RDU version history

 

Russ