I am planning on moving some drives around in my sever, helping me keep up with what is stored on each drive.  I want to align drive numbers with slot numbers in my server.  Previously you would have to stop the array, and you could move drives one position (IE swap two drives with each other), then start the array, and repeat this for every change.  In other words you could only assign one at a time and keep stopping/starting till you had it right.  Is this still the case with 5.0 or can you now move more than one at a time?

I would (a) do a parity check to confirm all is okay -- be sure any errors are corrected;  and then (b) simply do a New Config and assign the drives in the order you want.    Be CERTAIN that you assign the correct parity drive (and cache if you have one).    Also, as long as you're POSITIVE you have done NO writes to the array after the final parity check, you can check the "Trust Parity" box and eliminate the need to do a parity sync with the New Config.

 

I would (a) do a parity check to confirm all is okay -- be sure any errors are corrected;  and then (b) simply do a New Config and assign the drives in the order you want.    Be CERTAIN that you assign the correct parity drive (and cache if you have one).    Also, as long as you're POSITIVE you have done NO writes to the array after the final parity check, you can check the "Trust Parity" box and eliminate the need to do a parity sync with the New Config.

 

Is doing a new config any more than stopping the array and re-organizing the disks, then re-starting?  I'm actually in the process of replacing a 2TB disk with a 3TB disk, so let me know if this sounds right.

 

- Complete preclear process of new 3TB disk (hopefully tomorrow sometime).

- Replace 2TB drive with 3TB drive - let data re-build

- Run at least 1 preclear on old 2 TB disk confirm no issues.

- Assign old 2 TB drive to slot and the end of the array / format.

- Run parity check

- stop array - reorganize all drives at once

- check "trust parity" box and restart array

- run parity check

 

Does this sound right?  no one will be writing to the array during this process between completion of the 1st parity check and the 2nd.  I can be certain of this.

 

The 5.0 release recognises disks by serial number, not by where they are plugged into the server.  Moving the disks around physical slots will have no effect on the GUI order.

 

As I see it, that leaves you with a couple of options:

• Move the disks to positions so that their physical position matches their existing GUI order.  If you use this approach then there is no need to make any configuration changes and parity remains intact.  This means there is no risk involved through accidentally making the wrong configuration change.  The biggest risk would be disturbing connections during the physical move of the drives.
  
• Use the New Config approach to define a new order in the GUI.  This could be done before you actually physically moved any disks if so required.  It is probably the best way to go if you do not want to physically move the drives, but merely get the GUI to reflect the existing physical position. If you have not physically moved disks to their new positions before setting up the new config then it will be safe to trust parity.

Does this sound right?  no one will be writing to the array during this process between completion of the 1st parity check and the 2nd.  I can be certain of this.

 

Yes, that will work just fine.    The New Config / Trust Parity is simply the quickest way to get all the disks listed in the order you want.  The actual order makes no difference to v5 ... but it can indeed be convenient if it correlates with the positions of the disks in your case (mine do as well).

 

Use the New Config approach to define a new order in the GUI.  This could be done before you actually physically moved any disks if so required.  It is probably the best way to go if you do not want to physically move the drives, but merely get the GUI to reflect the existing physical position. If you have not physically moved disks to their new positions before setting up the new config then it will be safe to trust parity.

 

Is this fairly straightforward or is there a step by step for using the new config approach?  I have the same issue where I would like for my physical drives to match the order they are displayed in the GUI.  Is this just a matter of stopping the array, changing the disk configuration in the unRaid disk array menu and then starting the array and forcing parity to be trusted?

Is this just a matter of stopping the array, changing the disk configuration in the unRaid disk array menu and then starting the array and forcing parity to be trusted?

 

It is indeed very straightforward, but there are two important cautions ...

 

(1)  Be CERTAIN that the array is good before you start.  Do a correcting parity check, and be sure there are NO errors and NO sync errors (i.e. everything's zero)

 

(2)  Be CERTAIN that you know which drive is parity and (if you have one) which is the cache drive.

 

Then it's just as simple as you noted.  Just Stop the array; go to the Utils tab; click on New Config;  and assign the drives in the order you want them, and click on the "Trust Parity" box before you start the array.    Done :-)

 

 

Is this just a matter of stopping the array, changing the disk configuration in the unRaid disk array menu and then starting the array and forcing parity to be trusted?

 

It is indeed very straightforward, but there are two important cautions ...

 

(1)  Be CERTAIN that the array is good before you start.  Do a correcting parity check, and be sure there are NO errors and NO sync errors (i.e. everything's zero)

 

(2)  Be CERTAIN that you know which drive is parity and (if you have one) which is the cache drive.

 

Then it's just as simple as you noted.  Just Stop the array; go to the Utils tab; click on New Config;  and assign the drives in the order you want them, and click on the "Trust Parity" box before you start the array.    Done :-)

 

Excellent!

 

I do keep a drive map of where each one is located in the case, what drive letter it is assigned too, and what shares I use it for.  Over time of adding up to 10 data drives they are not organized as well as they once were so I am straightening that out.

 

So after saying trust parity, do I rerun a check and if so, what if error come up?

 

 

Sent from my iPad using Tapatalk

If you haven't made any errors, then when you "Trust Parity" the next check will be clean.

 

But if it's not, then it will simply correct the parity to match the data -- no big deal.

 

If you haven't made any errors, then when you "Trust Parity" the next check will be clean.

 

But if it's not, then it will simply correct the parity to match the data -- no big deal.

 

OK, I went through this process.  To be clear:

 

I did run a parity check with no errors, all zeros. 

I hit the new config button.  Re-assigned the drives, and checked "Parity is good"

When I started the array, it automatically started a parity check with the write corrections box checked.  It immediately started finding 10K+ errors and continuously climbing.  I stopped the parity check.  My drives were all fine, data appears to be there (obviously can't verify it all). 

 

Is this normal? It would seem to make sense that it basically had to re-built parity but I thought checking that box would fix that.  Should I let it run a parity check writing corrections?

 

Something isn't right ==> the parity check after the new config should be "clean" ... i.e. no errors.

 

The only way I can think of that wouldn't be the case is if (a) you wrote to the array after doing the last check, but before you did the new config;  or (b) you made a mistake with your drive assignments (perhaps switching the parity and cache assignments).

 

At this point there's nothing you can do but just let it rebuild parity (either a correcting check, or another New Config without using "Trust Parity").

 

Are you SURE you used the "Trust Parity" checkbox ??  I think there's a "confirmation check" you also have to click on -- did you do that?

 

 

Something isn't right ==> the parity check after the new config should be "clean" ... i.e. no errors.

 

The only way I can think of that wouldn't be the case is if (a) you wrote to the array after doing the last check, but before you did the new config;  or (b) you made a mistake with your drive assignments (perhaps switching the parity and cache assignments).

 

At this point there's nothing you can do but just let it rebuild parity (either a correcting check, or another New Config without using "Trust Parity").

 

Are you SURE you used the "Trust Parity" checkbox ??  I think there's a "confirmation check" you also have to click on -- did you do that?

 

I figured it out  ...  all is OK but PO'd at myself for carelessness.  (IE could have been a serious mistake, just lucky it wasn't).

 

I have a 32 GB SSD that is my last drive in the parity line up.  When I re-assigned the drives, i totally forgot to assign that one and of course it started finding errors.  The first round auto corrected about 20,744.. so when i fixed the lineup and ran parity again (re-corrected) only to about 20,744, and then restarted parity check once again.  This time, no errors well past the 20,744 mark.  So it was the missing drive.

 

So I think i'm good now, thanks for the help.

 

 

Glad it was something simple !! 

By the way, that's (I suspect) why the parity check is automatically run after you do a "Trust Parity" option.  It will catch you if you "lied" (i.e. made a mistake in your assignments so it's not true that parity is still good).    Fortunately, simply leaving out a drive from the list of assignments doesn't cause any actual data issues ... it just results in a bit of "at risk" time for the array until you get parity back to its "good" state.

 

By the way, that's (I suspect) why the parity check is automatically run after you do a "Trust Parity" option.  It will catch you if you "lied" (i.e. made a mistake in your assignments so it's not true that parity is still good).    Fortunately, simply leaving out a drive from the list of assignments doesn't cause any actual data issues ... it just results in a bit of "at risk" time for the array until you get parity back to its "good" state.

 

Thanks for all the help.  check still going great here.  If something comes up I'll report it here, but not expecting any issues.