500 GB External Hard Drive - how safe

I've heard and read conflicting information concerning the reliability of500GB

and higher external harddrives - is this true? ARe 320gb more dependable. I'm

trying to select between Seagate and WD, 320 or 500? Thanks.........

I don't see bigger hard drives as any less safe as smaller ones. They just stick more platters in there. But they've been doing multi-platter drives since about 60GB, it's just that each platter holds more and more.

 

The bottom line is that if you're concerned about integrity and backup, get multiple, and use something like karen's replicator to keep everything in sync. I have my workstation backup to a server which does alternate night backups to 2 different external drives. And the serer is RAID 5 so I can have 1 drive fail and still be okay.

 

allan

With LaCie's 500gb external drives going for just over 100 bucks each, I just buy them in pairs and double-backup everything. No worries at all; if one should fail I'll just duplicate the backup.

<<They just stick more platters in there>>

 

This is not true, especially when talking about Seagate's perpendicular-bit drives.

what he says is very true

I , after some sad experiences finding cd-r backups as unreadable,

rI lookd up opinions on the www and found the life of recorded medial to be short.

 

unless you can make commecial cd's - not cd-r

s you are better off with manetic media. such as a hard drive.

I have had experiences magnetic media like floppies failing " as I walked accrosws the room" and my old tape backups colorado qic-80 -- dc2120 tapes failing, i think the best is to make extra backups

my wife keeps records for 2 non-profit organizations and makes multiple copies in different formats.

I've had bad luck with two different 100 GB externals - both failed within a year - so I don't see how 500 could be any worse. My current external - a Fantom - is the first one to last more than a year. FWIW, with the ones that failed I followed the manufacturers instructions and left them on all the time. With the Fantom I've only turned it on when I was using it despite the instructions to leave it on all the time.

Oh dear. It should be powered up all the time? Why do they have an on and off switch? I switch mine on and off all the time having never found instructions to do otherwise. Anyone one else have any info on this?

Hard drives will lose data eventually unless refreshed. The magnetic domains are not stable over long times.

 

You might well get 100 years out of good archival CDs and DVDs stored optimally. Cheap disks in sub-optimal storage conditiuons can fail in a few years. You're very, very unlikely to get 100 years out of a hard drive! Not only would they fail mechanically if you left them turned on, the magnetic domains would drift if you didn't refresh them. Magnetic tape has a life of maybe 30 to 100 years if stored properly. No better than good CDs/DVDs.

Rob,

 

doh - forgot about seagate's drives. My bad. But in general... :-)

 

allan

If you don't want to go the RAID route, a better solution than a single big drive might be a pair of external drives from different vendors. If you get two identical drives, and both turn out to be from a bad batch, you could be in trouble. Buying from different companies lowers that risk. It's uncommon, but has happened in the past; google "IBM Deskstar" for one case. That drive was very quickly nicknamed the Deathstar by computer geeks for a good reason. (I also use DVDRs from two different companies for the same reason. A bad batch can't ruin both full copies that way.)

 

Also, two big killers of hard drives are heat and movement. Set the drives where they'll have good ventilation with cool air and where they won't be knocked over or be subject to vibration.

 

Until I can afford to build my dream RAID server, this is the backup strategy I use. Dual external drives backed up nightly, and dual copies archived to DVDR each month, all from different vendors. Maybe I'm paranoid, but as they say, even paranoids have enemies.

Refresh the hard drive?

Yes. To refresh the data you read and rewrite all the data on the drive.

 

See SpinRite for example - http://www.grc.com/sr/spinrite.htm

some might argue that ECC error correction will refresh weak domains but I'm dubious. plan on periodic wipes and rewrites on your backup drives.

"... conflicting information concerning the reliability of500GB and higher external harddrives... "

 

Don't worry about it (if you manage the storage correctly.) The simplest thing to do is to buy two drives and do a periodic drive to drive copy. This by itself will give the bulk of benefits of more sophisticated storage schemes.

 

It doesn't matter whose external drive you buy. Regardless of packaging, there are only a single handful of drive manufacturers left. For backups, it's best to just buy a bare Seagate or WD and use a USB/SATA dongle for the transfer.

 

For all practical purposes, magnetic integrity of the data is the least of your worries. These things are designed to be robust, from the read channel all the way up to the control firmware.

 

Drive mechanicals are a bigger vulnerability. Keep perspective though: the latest Hitachi 1TB enterprise SATA drive is rated for 136 year MTBF. If it doesn't break in the first couple of weeks, it probably won't for the next 7 years (and this may as well be forever.)

Bob, Andy, Robert, thanks so much for explaining that, I was about to give them another beer.