New HDD, some files bad, fluke or?

Discussion in 'General Hardware' started by Son Goku, Dec 31, 2005.

  1. Son Goku

    Son Goku No lover of dogma

    Sometime back, and to finish some labs for a given class, I ended up needing to get an external USB based HD to copy the files over. It was an Active Directory class, and the respective Windows Server 2003 installations were in Virtual PC. Needless to say, those virtual HDD files present too much data to easily move.

    Anyhow, having 100 GB of external storage, I have since attached it to my PC for more storage, reformatted, etc

    However, going to watch some television shows I downloaded, 3 files showed up in Windows media player as codec unknown (not true, as they used the DIVX codec, and part 1, all of which were in the same directory played fine). Another download showed up as corrupted and wouldn't play. However all other downloads to that drive have worked fine. On the download that presented the 3, at least now (though previously unknown) bad files, Azureus noted that one IP address kept sending bad data (hundreds of times as I remember) and banned them from continued upload to my PC. It could be because of that (though one would think that with a detected bad packet, it would get it again).

    Does this sound like I should be concerned about the hard drive, a fluke, or what?

    Edit: BTW, I opened the tracker back up in the bit torrent program, after deleting the errant files. It's a 1.34 GB download or so, so it will take awhile before I can see if fresh copies will pose the same problem again or not.
     
  2. Steevo

    Steevo Spammer representing. Political User Folding Team

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    I have had problems with some sites and corruped downloads of video or audio, for me it was the number of requests sent to the site. I had firefox making 40 requests as my net can handle the speed, but if their server tries to run multiple concurrent connections (sp) and fails you end up with a corrupted download.
     
  3. Son Goku

    Son Goku No lover of dogma

    Yeah, I'm not sure what happened, and I wouldn't be wondering so much if

    1. I haven't had this problem with bit torrent downloads before

    2. The drive is only like 3 weeks old, and hasn't seen that much use (hardly any software is installed on it, as most stuff was on my primary drive which is in my PC and attached through the SCSI controller). New hardware always presents an unknown quantity.

    3. 2 seperate downlaods experienced problems

    First is as I mentioned. 3 files were bad, there were like 20 or so files in all. (It was a season of Doctor Who episodes, about 4 files to an episode.) The first was fine, the last 3 in the directory are bad now. Though whether they were bad to begin with I have no way of knowing. I checked some of the other files (from other eps, which also seem OK.) In this case, all 3 files weren't seen as DIVX files, so now sound would play, though there was video which looked OK. Perhaps it was some header info that identified the file that was in fact corrupted?

    Second one was in MPEG4 format, and Quicktime player wouldn't even load the thing claiming the file was corrupt, and trying to load it in another media player resulted in the player just locked up, and I had to kill process from Task Manager.

    Two possible liklihoods I can think of, but don't know the truth of it.

    - The extreme number of errors (odd that Azureus didn't ban the IP sooner, as it's set to auto-ban after so many bad data transmissions which is usually under 12, not like 700, which is what it was in this one case) was so bad, that the error handling built into my own client was simply over-whelmed and unable to recover. Though if that was the case, not sure it would just be these 3 files and the others do seem OK. Torrents aren't loaded sequentially, as all files are broken up into pieces and then blocks, all of which can be downloaded from different IPs in any order.

    - The file was good, and perhaps my hard drive goofed up

    Beyond that, I'm not sure how I would isolate it after the fact, as I obviously have no way of knowing if those 4 files (3 from the 1 download, and then the other) were ever good...

    Perhaps it would be a good idea to test the drive, but would a chkdsk /f be enough to know for certain, or is there something else I should run against it? Or is it just one of those things I'll need to keep an eye on to see if anything further happens?
     
    Last edited: Dec 31, 2005
  4. LeeJend

    LeeJend Moderator

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    I've had bad bit torrent downloads from links that friends used with no problem. On subsequent downloads the files were good. This should not be possible with bit torrents error correction but...

    On the other hand I had in the past a problem with data corruption to an external drive. Subsequently I've used it with a different HD installed and it handles 60 gigs of data transfer in and out without a problem. This was a very cheap enclosure and attached to a PC with quirky USB.

    Hope my contradictory answers helped ;)
     
  5. Steevo

    Steevo Spammer representing. Political User Folding Team

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    Yeah, try chkdsk and see what that turns up. I doubt seriously that the IP would be banned if you were the only one who was having problems. It's possible that the packets were damaged but still passed checksum or that they were assembled incorrectly by the handler. Or somewhere between you and said IP address there is a network problem.

    There are lots of possibilitys.
     
  6. Son Goku

    Son Goku No lover of dogma

    Oh, when I say banned, I mean by my computer, not the tracker. You see with the lattest version of Azureus (my client) it keeps track of what users sent bad packets, and also has an "auto-ban" feature that is built in.

    When a given IP sends bad data in excess of so many times, the software itself auto-bans the IP from further communication with it. Too many IPs in the same netblock suffer the same fate, then it auto-bans the IP address block. I usually clear that out sometime after the torrent they errored out on is finished, as well anyone can have a problem (bad nic that could get rectified), or the Internet between them and me could have a problem. Usually there is an IP or a couple that come up in a given download (though not always the same ones).

    Part of the reason why I'm also wondering about the drive is this. Having to re-download something in the size of GBs worth (let along re-upload to bring my share ratio back up with aDSL) is annoying yes, but to free up space on the main drive, I was looking to start moving some of my data over.

    Thus far I have only moved stuff that I can download again (like winXP SP download, and device drivers), hesitating until I know the drive is good at moving non-recoverable data (minus a backup of course, which isn't as easy as the data directory continues to grow). Though with a DVD burner, it's not so massive that a DVD-RW would be beyond feasability for backing up, though a CD has been way too small for years now.

    After this, I'm more hesitant, rather then less to complete the moving of my data to this new drive.

    I'll try chkdsk after it finishes up the current download (which has 4.53 GB left) and I've got an acceptible share ratio. If someone thinks there's another prog for testing this which I should also run, then that also?
     
  7. Son Goku

    Son Goku No lover of dogma

    Maybe those 3 files had gotten corrupted in the torrent somehow. The re-download finished, and the same exact problem, on the same exact files, with the same first one working. Random errors don't tend to repeat in such a logical fashion...

    I guess perhaps I need to report the problem on the tracker, in which case the person can decide whether to re-upload, others can mention if they're seeing it too, at the very least people can know ahead of time before spending time trying to get it.