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LTO 6 space occupying issue.
I have been using the IBM TS2260 3580 H6S HH Drive from 2014. From last week I am getting an issue with the space in the tape media. While I am copying data to LTO 6 media I am getting a message saying that there is no space left after copied around 1.5tb sometimes, 1.2tb sometimes. The properties of the copied data showing right amount but, properties of the tape showing full. I usually work on mac os x. Tried with mac os x and windows 10 also. Yesterday I have also run the ITDT health test. But performance showing error, remaining everything passed. I never used any backup application. Going through the terminal commands from the beginning itself. Tried replacing the cable also. But no luck. Any solutions?
HARI KRISHNA PUNE
FCP EDITOR & ARCHIVE MANAGER -
20 Replies
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The LTO specification requires that after a write is done then immediately following that the read heads read the data back and check if it is written properly and if not the data is written out again and a “soft error” is recorded and this process can repeat up to 16 TIMES before it gives up and records a “hard error” so the data may be eventually successfully written but there could be a lot of bad writes taking up a lot of space in between and as long as this is <16 then you probably would not notice there’s a problem until you notice that you can only write significantly less data to the tape itself like you mentioned.
I suggest you check the soft error numbers as you could have millions or billions of them and if you do then this usually indicates that you have dirty heads that need cleaning or worn out heads that need replacing, however, since the tape heads reputedly cost around a quarter of the cost of a new tape drive it is not really cost effective to repair it with replacement heads and you may as well buy another tape drive. If this is not the cause of the problem then I don’t know what else it could be as the LTO tapes have servo tracks on them to make sure that the heads are positioned on the actual tape track correctly.
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@Jerzy Zbyslaw
Thanks for your quick reply. I am not a professional to understand the coding language. Forgive my ignorance and please explain check soft error numbers. Thank you.HARI KRISHNA PUNE
FCP EDITOR & ARCHIVE MANAGER -
Hello, usually the backup software will tell you as part of the log of data written to the tape as to how many soft and hard errors have occurred and here is an example for Backup Exec https://www.veritas.com/support/en_US/article.100020857 notice that it only has 857 soft errors which is a low amount and can be disregarded.
Since you mentioned that you are using an IBM tape drive then what you should do is download the IBM tape diagnostic tool and see what information you can obtain from that, you can download it here https://www.ibm.com/support/knowledgecenter/en/ST9MBR_1.2.5/ltfs_itdt_download.html
There is always the possibility that there is nothing wrong with the tape drive unit itself and it may be the tape in the cartridge that is the source of the problem especially if it is old and has been re-used many times but this is easy to check because if you then use a new tape cartridge it should store close to the full amount possible so check this as well that your old tapes are not worn out, if the tape heads are the problem then it will store like you said “1.5tb sometimes, 1.2tb sometimes” on both old and new tapes.
Either the tape heads need cleaning and haven’t been cleaned for a while in which case you will need to clean them with a cleaning cartridge or they are going bad and here is a previous discussion with similar problems that you had and it was diagnosed that in that particular case the tape heads were actually bad https://forums.creativecow.net/docs/forums/post.php?forumid=330&postid=654&univpostid=654&pview=t What is the cause with your situation I do not know, it could be any of these problems.
Cheers
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Hi, Thanks for your explanation. Yeah you are right, If I am using an backup application I may know about the soft errors. But in my case I am not using one.
I ran the health test & full write test using IBM tape diagnostic tool a while back. Please see the attached images for the test results. I ran the test multiple time by changing the drive firmware also. Still stuck with Performance failed message.
As you said it might be the issue with the tape – for that I am not using any old tapes here in this case. All the tapes are brand new. Also providing the consistency check and rollback pics. Please refer.
And in the matter of cleaning head I never did it on purpose, But I did it when ever my drive shows an error code “C” in the single character display. After got this issue I have seen an post from another blog and tried to hard clean with multiple times. Still getting the same issue. Yesterday I tried running cleaning cartridge for up to 10times and then make some data transfer. And the result is I have copied the data of 1.1TB and is showing that 1.35TB occupied in the tape.
HARI KRISHNA PUNE
FCP EDITOR & ARCHIVE MANAGER -
Unfortunately, I have no idea what is wrong with the drive and at this point I can only suggest that you first post your last reply on the public IBM forum and see if someone else can diagnose the issue https://www.ibm.com/developerworks/community/forums/html/topic?id=1eac1dfe-7eeb-4e9e-8036-fe3668fb54d7 or alternatively contact IBM support directly https://www.ibm.com/support/home/product/5301452/Tape_Drive
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@Jerzy Zbyslaw
Thanks for the suggestion. I will follow the path and let’s try.HARI KRISHNA PUNE
FCP EDITOR & ARCHIVE MANAGER -
I forgot one thing to mention. So bad. At first I started to notice some line in the terminal window while I format a tape. While formatting the tape at the bottomline of “writing index to a”, “writing index to b” I noticed a line saying “failed to release the advisory block”. Have any one seen this before?
HARI KRISHNA PUNE
FCP EDITOR & ARCHIVE MANAGER -
Are you writing to tape as LTFS?
Are you doing drag and drop (or copy-paste) in Win Explorer?
Or do you use some software to write to tape?Your signature says ‘FCP Editor’. So maybe you’re backing up Mac drives via a Windows machine?
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Neil Sadwelkar
neilsadwelkar.blogspot.com
twitter: fcpguru
FCP Editor, Edit systems consultant
Mumbai India -
@Neil Sadwelkar
Thanks for your concern. Yes, I am writing to tape as LTFS. And I am doing copy-paste in windows explorer. I am not using any software.
I am an FCP EDITOR. I have tried this with both mac and windows.
HARI KRISHNA PUNE
FCP EDITOR & ARCHIVE MANAGER -
We repair and refurb tape drives all day long at Magnext / MagStor.
I saw that you mentioned running a cleaning cartridge 10x times in a row. This is a big time no-no and can kill your drive head. Only clean when the light is on.
If you’re failing performance tests with good media, then your head is is usually going bad.
The way LTFS works, it can never give you an accurate capacity of the tape because each file you copy over writes a separate marker file.
Tim Gerhard
MagStor Inc.
614-505-6333
tgerhard@magnext.com
NAB 2018 Booth #SL15816
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