Should I trust failed verified DVD?

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I am backing up files on DVDs off my iMac. A few of them failed verification. However, the files show up in the DVD after I eject and put the DVD back in. Am I making a mistake to trust the DVD as a back up if the verification failed?

Also, I'm still searching online as I am burning the DVD. Is that okay?

Thanks
 

chscag

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I certainly would not be inclined to trust a file that failed verification. The verification procedure is normally just a CRC check, however, a file that fails to check OK may not work later on when you need it. And yes, it can appear normal on the DVD and fail the check.
 
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I certainly would not be inclined to trust a file that failed verification. The verification procedure is normally just a CRC check, however, a file that fails to check OK may not work later on when you need it. And yes, it can appear normal on the DVD and fail the check.


sigh.... great... I don't remember which one's verified and which ones didn't. :( MY FAULT.
 
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Is there anyway I can tell which verified and which didn't after the fact?

Another one didn't verify. I'm doing something wrong.
I'm just going to redo all the dvds and destroy these. What am I doing wrong?
 

chscag

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No, it would take a do over of the backup. I should have mentioned in my first reply that using DVDs to backup from your hard drive is really not recommended. Not only is the procedure slow, but there is always the chance that the restore may fail because of a bad copy. However, backing things up like movies, music, and especially photos are fine. Complete backups though should be made to an external hard drive using Time Machine.
 

cwa107


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No, it would take a do over of the backup. I should have mentioned in my first reply that using DVDs to backup from your hard drive is really not recommended. Not only is the procedure slow, but there is always the chance that the restore may fail because of a bad copy. However, backing things up like movies, music, and especially photos are fine. Complete backups though should be made to an external hard drive using Time Machine.

+1 for this. There was a time when backing up to optical discs was the only cost-effective way to do so. Nowadays, external hard drives are fairly cheap (although they're kind of expensive at the moment due to a supply shortage caused by flooding in Thailand) and most backup software is geared toward backing up to an external.

Time Machine makes backups brain dead simple. Plug in the external, set it and forget it. You're completely covered. And you'll never have to hassle with squeezing only a few files on optical discs.

Another thing to keep in mind is that writeable discs DO degrade over time. Even the best quality discs have a limited shelf-life (usually around 7-10 years).
 
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I lost the power supply for my SeaGate TB. So until I get the new on next week I wanted to just back up some websites and photos folders on the DVD. I had one external TB that went back on me. Is it a good idea to continue to use that one? After all, it was probably just a part of the hard drive that went bad.
 

IWT


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Hi MacLover

If and, I hope, when you get round to backing up to Time Machine, here are links to step-by-step instructions for doing this and for recovering from TM as well.

For your situation TM is the way, as stated above. Settings, preferences, everything is backed up in the background, hourly etc. Set up and forget.

Good luck.

Ian

Mac 101: Time Machine
How to restore a hard drive using Time Machine | Macworld
http://www.macworld.com/article/164...ow_to_set_up_time_machine.html#lsrc.rss_howto
 

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