Just installed unMenu beta 1.3 (awesome addon). playing around with the new options I came across this on the SMART page for my parity drive:

 

» reallocated_sector_ct=2

» reallocated_event_count=2

 

The wikipedia entry beneath is saying it's a possible indicator of imminent failure! Do I need to replace the drive ASAP, or is it not actually something to be concerned about yet?

 

Thanks in advance!!

 

Justin

Just installed unMenu beta 1.3 (awesome addon). playing around with the new options I came across this on the SMART page for my parity drive:

 

» reallocated_sector_ct=2

» reallocated_event_count=2

 

The wikipedia entry beneath is saying it's a possible indicator of imminent failure! Do I need to replace the drive ASAP, or is it not actually something to be concerned about yet?

 

Thanks in advance!!

 

Justin

You need to read a LOT more.  Most drives these days have several thousand spare sectors.  What you need to watch is if the number of re-allocated sectors starts creeping up over time.  I have one drive in my array that has the same 100 sectors re-allocated since I first ran a smart report on it several years ago.  It is fine as long as the number does not start rising.

 

Look at the smart report itself.  You will see a line i in for the Re-allocated sectors.  It will have a many fields.  The first is the current "normalized" value, then the worst "normalized" value (typically the same for this attribute)

Then the next column is a threshold. If the normalized value goes below the threshold then that attribute will have FAILED.

 

Please post the numbers on that line for your drive.  I think you'll see the drive is nowhere near failing.

ID# ATTRIBUTE_NAME          FLAG    VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE

 

  5 Reallocated_Sector_Ct  0x0033  100  100  005    Pre-fail  Always      -      2

 

Thanks for the quick response Joe - is that the line you're after?

 

Justin

ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE

 

  5 Reallocated_Sector_Ct   0x0033   100   100   005    Pre-fail  Always       -       2

 

Thanks for the quick response Joe - is that the line you're after?

 

Justin

Exactly... when the normalized "100" value drops below "5" then you are close to running out of sectors to re-allocate.

 

Now that you've installed unMENU, you can keep an eye on all your disks over the next few months... 

 

Glad you like unMENU.  It does provide lots of information on your server.

 

Joe L.

Many thanks Joe - put my mind at ease and learnt something in the process!

 

Having a play with installing some of the packages. Would like to to get the email notifications working but looks like that needs the compilers etc. Will tread carefully

 

Justin

Many thanks Joe - put my mind at ease and learnt something in the process!

 

Having a play with installing some of the packages. Would like to to get the email notifications working but looks like that needs the compilers etc. Will tread carefully

 

Justin

Ah yes, but one of the packages installs the compiler and tools needed.  Just download and install it first.  You don't need to set it to re-install every time you reboot, just install it once.  Then install the mail program.

 

Now, you still need to put into place a program monitoring the array health, to actually send the mail... but that is another add-on.

 

Joe L.

That addon isn't in unMenu for download though is it?

Ah yes, but one of the packages installs the compiler and tools needed.  Just download and install it first.  You don't need to set it to re-install every time you reboot, just install it once.  Then install the mail program.

 

AH!

Thanks for clearing that up.  It should have been obvious but for some reason i though I had to have the compiler code always running so I was staying away from the mailer too.  Good to know - Thank You.

A few or even a few hundred reallocated sectors is not really a problem.  But experience here has shown that even 1 or 2 reallocated sectors is a predictor of increased reallocated sectors on neary every parity check.  It's almost like a string on a garmet and once you start pulling on it, the garmet falls apart.

 

I'd suggest starting to run very frequent parity checks - every day or every other day.  If after 4-5 parity checks the number has held steady at 2, I'd feel comfortable that the drive is stable and the the 2 reallocated sectors are isolated and not a problem.  But if the number increases you need to keep running parity checks until you get at least 4 consecutive parity checks with NO increase in reallocated sectors.  If they start to creep upward and you find you've run 10-20 parity checks and the reallocated sectors keep going up, the drive will never by reliable IMO.

 

If the count starts incrementing, the tricky part may be getting it to report enough reallocated sectors to qualify the drive for RMA replacement.

 

BTW, I noticed that on older generation drives the number of reallocated sectors would frequently stabilize and not increase, but in drives >= 500G, I have seen very few that have a stable number of reallocated sectors.