Re: [gentoo-user] Testing a used hard drive to make SURE it is good.

[Dale]

Mark Knecht wrote:
>
>
> On Mon, Jun 15, 2020 at 12:37 PM Dale <rdalek1967@×××××.com
> <mailto:rdalek1967@×××××.com>> wrote:
> >
> > Howdy,
> >
> > I finally bought a 8TB drive.  It is used but they claim only a
> short duration.  Still, I want to test it to be sure it is in grade A
> shape before putting a lot of data on it and depending on it.  I am
> familiar with some tools already.  I know about SMART but it is not
> always 100%.  It seems to catch most problems but not all.  I'm
> familiar with dd and writing all zeores or random to it to see if it
> can in fact write to all the parts of the drive but it is slow. It can
> take a long time to write and fill up a 8TB drive. Days maybe??  I
> googled and found a new tool but not sure how accurate it is since
> I've never used it before.  The command is badblocks.  It is installed
> on my system so I'm just curious as to what it will catch that others
> won't.  Is it fast or slow like dd?
> >
> > I plan to run the SMART test anyway.  It'll take several hours but
> I'd like to run some other test to catch errors that SMART may miss. 
> If there is such a tool that does that.  If you bought a used drive,
> what would you run other than the long version of SMART and its test? 
> Would you spend the time to dd the whole drive?  Would badblocks be a
> better tool?  Is there another better tool for this?
> >
> > While I'm at it, when running dd, I have zero and random in /dev. 
> Where does a person obtain a one?  In other words, I can write all
> zeros, I can write all random but I can't write all ones since it
> isn't in /dev.  Does that even exist?  Can I create it myself
> somehow?  Can I download it or install it somehow?  I been curious
> about that for a good long while now.  I just never remember to ask.
> >
> > When I add this 8TB drive to /home, I'll have 14TBs of space.  If I
> leave the 3TB drive in instead of swapping it out, I could have about
> 17TBs of space.  O_O
> >
> > Thanks to all.
> >
> > Dale
> >
> > :-)  :-)
>
> The SMART test, long version, will do a very reasonable job catching
> problems. Run it 2 or 3 times if it makes you feel better.
>
> Chris's suggestion about Spinrite is another option but it is slow,
> slow, slow. Might take you weeks? On a drive that large if it worked
> at all.
>
> As an aside, but important, I fear that you're possibly falling into
> the trap most of us do at home. Please don't. Once you have 17TB of
> space on your system how are you planning on doing your weekly
> backups? Do you have 17TB+ on an external drive or system? Will you
> back up to BlueRay discs or something like that?
>
> Mark


Way back, we used Spinrite to test drives.  Think mid 90's.  Yea, it was
slow then on what today is a tiny hard drive.  Can't imagine modern
drive sizes.  It is good tho.  It reads/writes every single part of a
drive.  It will generally find fault if there is one. 

Right now, I'm backing up to a 8TB external drive, sadly it is a SMR
drive but it works.  As I go along, I'll be breaking down my backups. 
Example.  I may have my Documents directory, which includes my camera
pics, backed up to one drive.  I may have videos backed up to another
drive.  Other directories may have to be on other drives.  The biggest
things I don't want to lose:  Camera pics that could not be replaced
except with a backup.  Videos, some of which are no longer available. 
That requires a large drive.  It currently is approaching 6TBs and I
have several videos in other locations that are not included in that. 
Documents which would be hard to recreate.  Since I have all my emails
locally, I don't want to lose those either.  Just a bit ago, I was
searching for posts regarding smartctl.  I got quite a few hits.

Even if I build a NAS setup, I still need a backup arrangement.  Even if
I have a RAID setup, still need backups.  It gets complicated for sure. 
Sort of expensive too.  Just imagine if my DSL was 10 times faster. 
O_O  I'd need to order drives by the case.

Dale

:-)  :-)