derald Posted June 23, 2005 Report Share Posted June 23, 2005 Configuration: G5 PowerMac dual 2Ghz, OS X 10.4.1, Retrospect 6.0.212, DU 6.4.102, Exrix VXA-1 Tape Drive w/FireWire with the latest firmware. I did two archives to a tape and a redundant tape under Panther with Retrospect 6.0.204 and had been able to retrieve files. After upgrading to Tiger and installing the Retrospect upgrade I did another archive to each tape and it ran successfully. When I tried to retrieve some files it said showed, "Tape Unrecognized". I went to my redundant tape and it did the same thing. I have called Retrospect support three times and Ecrix two times to resolve the issue. So far I have deleted the Retro Config, reverted back to Panther and Retro 6.0.204 on another Mac, tried to rebuild and repair the set from the tape, and recorded and retrieved with a new tape to ensure the drive works, but the tapes are not recognized. I believe the tape drive works properly and the it is highly unlikely that the both tapes would go bad at the same time. It seems that the header file was corrupted during the switch from Panther to Tiger. I cannot spend thousands of dollars having the files recovered from the tape. Is there something I can do to restore the tapes or correct the header file? Help! Quote Link to comment Share on other sites More sharing options...
natew Posted June 28, 2005 Report Share Posted June 28, 2005 Hi Is it only these two tapes that cause problems or do restores from any VXA tapes fail? Do you have the same problem if you run a backup to a new tape and then try to restore from it? At first glance I'd say this is a hardware problem. The tests above will help establish that. Thanks Nate Quote Link to comment Share on other sites More sharing options...
derald Posted June 28, 2005 Author Report Share Posted June 28, 2005 Nate, I am able to backup and restore from a new tape. Derald Quote Link to comment Share on other sites More sharing options...
natew Posted June 29, 2005 Report Share Posted June 29, 2005 Hi How about other old tapes? Once a header is written Retrospect will only read it for normal backup operations. It will not write to the header in any way unless you do a recycle backup. That said, changing from Panther to Tiger will not make any difference as far as the header information is concerned. Is it possilbe that these two tapes were stored together and exposed to a common environmental factor that damaged them? Thanks nate Quote Link to comment Share on other sites More sharing options...
derald Posted June 29, 2005 Author Report Share Posted June 29, 2005 Nate, I only use the old tapes for restoring, because they are from the first set of client files. I can restore from any of them. New tapes will backup and restore. The problem occurred after I did my first backup with Tiger and the updated Retrospect. The tapes are stored in different places. One is stored in my office which is temperature and humidity controlled and it is out of any direct light. The other is stored offsite in similar conditions. As I mentioned, the tape drive works fine and I believe it is highly unlikely that two tapes would go bad at exactly the same time. Also, if I try to do a restore from the tape it shows up as "Tape Unrecognized" and Retrospect instantly reports "Exection Completed Successfully" as soon as I hit the "Retrieve" button. Thoughts? Quote Link to comment Share on other sites More sharing options...
natew Posted June 30, 2005 Report Share Posted June 30, 2005 Hi How old are the tapes and how many times have they been used? Were the two backups performed on the same day? The "content unrecognized" means that Retrospect simply cannot find any recognizable header information on the tape. If you know someone with another VXA drive you could try a restore there. Otherwise your only choice will be data recovery. Sorry, Nate Quote Link to comment Share on other sites More sharing options...
derald Posted June 30, 2005 Author Report Share Posted June 30, 2005 The tapes are approximately 8 months old and have only had three backups done to each tape. Yes, they were done the same day. The issue is not with the tape drive. It works fine. This issue in my opinion, is the way Retrospect wrote to the tape with the latest Tiger update when I upgraded to Tiger. All indications point to the software not the hardware. Am I the only one on this forum or calling in to the support line with this problem? Derald Quote Link to comment Share on other sites More sharing options...
natew Posted July 1, 2005 Report Share Posted July 1, 2005 Hi The thing is, nothing changed in the way Retrospect writes to tapes in Panther or Tiger. I'm not making excuses here, its simply a fact. Tapes work differently than just about any other media type. Let me try to explain why what you are proposing isn't possible: In your case you are getting a "content unrecognized" message. That means: a)Retrospect sees the tape in the drive b)The tape drive has positioned the tape c)Retrospect was not able to locate a valid header on the tape Long story short - Everything is working right but the header appears corrupt or damaged. So what can corrupt/damage a tape header? On the average tape drive you have a read head and a write head. To write to a tape the write head must be engaged. Likewise the read head is engaged to read the tape. The read head can't write. The write head can't read. In the first backup to a blank tape Retrospect engages the write head, writes the header information on the tape and then continues writing data to the tape. On the second, third, fourth... backup _only_ the read head is used to check the header information of the tape and position the tape to the last point where data was written. From there the write head engages and writes data to the tape. Even when the tape gets full the header information is not updated. My point is this: Retrospect physically cannot corrupt a tape header with the read head. No application can. Unless of course there is a problem somewhere with the tape or tape drive. That is why I sugest we look for other possible causes. Thanks Nate Quote Link to comment Share on other sites More sharing options...
derekryan Posted July 1, 2005 Report Share Posted July 1, 2005 derald, Any luck with your tapes? I just bought 3 firewire VXA-2 and 3 mac minis to do my archiving to tapes. I am about to start testing them. When you archive to tape in Tiger and Retro 6.0.212 - can you retrieve it correctly? I am lucky because I did not used OS X for archiving yet. I was using OS 9 till now. Derek Quote Link to comment Share on other sites More sharing options...
derald Posted July 2, 2005 Author Report Share Posted July 2, 2005 Since the drive is able to write to and read to new tapes I must conclude that the drive is working properly. The problem occured after writing to the tape and then trying to retrieve. The corruption happened somewhere in those functions. I just find that the odds of two tapes going bad at the same time implausible. I have sent the tape off to data recovery and will be using external drives to archive my files as opposed to trusting Retrospect and tapes with irreplaceable files. Quote Link to comment Share on other sites More sharing options...
derald Posted July 13, 2005 Author Report Share Posted July 13, 2005 The determination by the data recovery service is that the block size has changed on the tape, and is unrecoverable. The media itself was determined to be fine. How does the block size on a tape change? Quote Link to comment Share on other sites More sharing options...
derald Posted July 13, 2005 Author Report Share Posted July 13, 2005 The data recovery company determined that the tape media is fine, however, the block size on the tape changed and all data is unrecoverable. How does the block size change? Quote Link to comment Share on other sites More sharing options...
derald Posted July 15, 2005 Author Report Share Posted July 15, 2005 The tape recovery company determined that the media is good, however, after examining the tape they have discovered that the block size has changed on the tape and is unrecoverable. What would cause the block size to change? Quote Link to comment Share on other sites More sharing options...
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