Another question : tape drive

[david at thekramers.net (David Kramer)]

On Friday 09 May 2003 08:00 am, Jerry Feldman wrote:
> I gave up on tapes years ago. I back up to a hard drive.

The deal breaker for tape backup in my eyes is not that tapes fail, but that 
you usually don't know about the failure at write time.  You can only know 
for sure that a backup was valid *at that time* by doing a full verify, which 
often takes longer than the backup.  And the odds that a tape will go bad 
just sitting there is much higher than for a hard drive or CD/DVD.

> IMHO, removable harddrives are better than fixed hard drives. In the
> past:
> I've had the tape drive (commercial 9 track) brun a hole trhough a
> backup tape. I've had PC tape drives trash my backups. My strategy is
> that 2 hard drives are not going to crash simultaneously (which is not a
> 100% valid assumption).

The only real risk of backing up to an internal hard drive is a hige voltage 
spike knocking out both drives, which is unlikely (but not impossible; a 
power supply failure could do it) if you're running on a UPS.

The only other downside is if you want to restore data from a while ago, 
you're more likely to have a tape archive.  You can rotate around several 
directories on your backup hard drive, but to store monthly or quarterly 
backups you need a removable hard drive like a firewire or USB2.0 hard drive.  
Or serial ATA.

One person I know has a mirroring RAID setup.  They leave the second hard 
drive off.  To back up, he activates the second drive, waits for the sync to 
finish, then takes the drive offline again.

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DDDD   David Kramer         david at thekramers.net       http://thekramers.net
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