The issue with USB Flash drives is they have a terminal Number of writes before they are done. With a USB HDD you have the nromal life expectancy of a HDD and i think in the long run it is a better idea. However Aside form that issue and the dangers of Cheap flash memory it should work just fine. On Mon, Nov 3, 2008 at 9:22 AM, Alan Dayley wrote: > On Mon, Nov 3, 2008 at 8:16 AM, Dan Lund wrote: >> I'd definitely have to side with the external hard drive scenario. >> While USB thumbdrives are real nice for the size they have a limited >> lifespan and can lose data much easier than a hard drive from >> electromagnetic interference. >> >> I still prefer Linus Torvalds' quote, "Only wimps use tape backup: >> _real_ men just upload their important stuff on ftp, and let the rest >> of the world mirror it ;)" >> lol >> >> Thanks, >> Dan Lund > > Flash is LESS susseptible to electromagnetic interference than hard > disk drives. I have personally tested degaussing coils that > successfully erased hard drives but did nothing to flash storage > drives. This is because hard disk drives use magnitism to store data > while flash uses capacitance, essentially. > > Data retention of flash is at least 5 years and some manufacturers > state retention times much longer than that. Sitting in a safe > deposit box enviornment, flash should not lose data. > > But, it all depends. ;^) > > There are, generally, two types of flash: multi-level cell (MLC) and > single-level cell (SLC). MLC can store two or more bits in a single > flash cell while SLC stores one bit per cel. Most consumer flash > drives use MLC flash because it is MUCH cheaper than SLC. But, > becuase of the mult-bit (read: multiple voltage level) nature of MLC, > it is far less data reliable than SLC. > > The rub is that there is not an easy way to find out if the flash > device you have is MLC or SLC except by price. SLC will be quite a > bit more expensive. SLC is also sold under a description of > "industrial" or "high reliability" and such terms. If what you have > was a good consumer price and does not have such terms attached to it, > it's MLC almost for sure. This is not to say that MLC is all bad. It > works well for situations like storing photos or operations where lots > of rewriting does not take place, like backups. ;^) > > Just remember, with flash media you DO get what you pay for. Buy a > well known brand link San Disk, Lexar, STech, Samsung, Toshiba, etc. > to get the highest quality possible. Don't skimp on price, especially > for data backup. The "off brands" do buy up low quality or even > rejected flash for use. This is usually not a big problem because if > a bit flips in one of 8 mega pixels of a photo, would you know it? > But if a bit flips in your ext2 filesystem inode tree, you may have > just lost something! > > I would have no problem depending on flash to store backups as long as > I used the best quality drives I could find. And they were in a > resonable refresh schedule like one would with tapes or hard drives > anyway. > > Check Sam's Club. They regularly have Toshiba USB sticks and other > flash media on sale for the price of bargan brands elsewhere. They > are good quality, in my experience. > > I love Linus' backup method too. But I'm no Linus Torvalds so must > use other methods. > > Alan > --------------------------------------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us > To subscribe, unsubscribe, or to change your mail settings: > http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss > -- A mouse trap, placed on top of your alarm clock, will prevent you from rolling over and going back to sleep after you hit the snooze button. Stephen --------------------------------------------------- PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us To subscribe, unsubscribe, or to change your mail settings: http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss