Shrinking Array

[johnestan]

Hi, can someone walk me though how to remove a disk from my array and rebuild parity. I moved my system into a new case and broke the plastic off a drive's sata connector in the process. I'm currently running my array with the missing disk emulated and therefore unprotected. I don't think there was any data on the missing disk. If I click view on the emulated disk, there are not any files. I'd like to just rebuilt parity with the disks I have while keeping all my data intact. Thanks. 

[trurl]

Tools - New Config, assign disks as you want and start array to begin parity build. Be sure you don't assign any data disk to any parity slot or it will be overwritten with parity.

[johnestan]

6 minutes ago, trurl said:

Tools - New Config, assign disks as you want and start array to begin parity build. Be sure you don't assign any data disk to any parity slot or it will be overwritten with parity.

So do I need to manually clear a disk in order to use it as the new parity disk after New Config without losing data?

[trurl]

You didn't mention a new parity disk. Are you planning to replace parity? Not that it really matters since the only point of preclear in this scenario would be to test a new disk. Unraid only requires a clear disk when ADDING a disk to a NEW data slot in an array that already has valid parity. This is so parity will remain valid since a clear disk is all zeros and so has no effect on parity.

 

You already said the disk you are removing had no data so assuming that is true then you won't loose any data since the other data disks will stay as they are. Each data disk is independent and parity has no data. Parity will just be built based on the disks you have assigned.

[johnestan]

11 minutes ago, trurl said:

You didn't mention a new parity disk. Are you planning to replace parity? Not that it really matters since the only point of preclear in this scenario would be to test a new disk. Unraid only requires a clear disk when ADDING a disk to a NEW data slot in an array that already has valid parity. This is so parity will remain valid since a clear disk is all zeros and so has no effect on parity.

 

You already said the disk you are removing had no data so assuming that is true then you won't loose any data since the other data disks will stay as they are. Each data disk is independent and parity has no data. Parity will just be built based on the disks you have assigned.

"parity has no data". Thanks that answers my question. I'll just do a new config and keep the same parity disk. Thanks for the help!

[MegaMustang]

I want to shrink my array as well, but i have a not yet assigned parity disk  as im still bringing terabytes of data over from my old rig and dont want parity slowing things down. i had to put a 3 tb disk in for a bit and now want to replace it with a 10tb disk. I already moved the data off the 3tb with a plugin called unbalance.   Is the procedure exactly the sane as if i had a parity disk?

Edited February 9, 2021 by MegaMustang

[trurl]

Without parity, you can't rebuild a replacement. if you remove a disk and put another in its place, the new disk won't have any contents, and the contents of the disk you are removing will not be in your system anymore.

[MegaMustang]

Thanks for your quick reply! I hope the contents of the disk im removing are in my system. took 5 hours for unbalance to move them to my other disk in my array. i look at the disk i want to remove using the unraid file browser and there appears to be no more data other than empty root folders and the other drives have taken the data on from that disk.

 

So, is the procedure the same (which it doesnt sound like by your reply) or is there something else i need to do to take the 3tb out and replace it with a 10tb? 

 

One other quick question, in doing a new config i shouldnt lose any of my dockers , plugins or their data right? Does a new config delete any of that? I would like to think a new config is just reassigning  what disks go where...but thats why im asking as im pretty new with unraid.

[trurl]

12 minutes ago, MegaMustang said:

new config is just reassigning  what disks go where

exactly.

 

And when you start the array, it optionally (by default) builds parity on any disk assigned to any parity slot.

[MegaMustang]

Great Thanks! Well i dont want any parity disk assigned as im still bringing data over. Do i just do what it says below from the new config page before i start the array?

"Preserve current assignments: pick ALL"

 

Also please confirm no data loss. It took me a bit to get all my dockers and plugins setup running perfect, and i dont feel like going through that again.

[trurl]

New Config will not affect the contents of any disk (except parity if assigned).

[MegaMustang]

On 1/10/2021 at 9:08 PM, trurl said:

Tools - New Config, assign disks as you want and start array to begin parity build. Be sure you don't assign any data disk to any parity slot or it will be overwritten with parity.

it looks like from your earlier post it will give me the option to assign or not assign a parity disk. 

[trurl]

You can assign or not assign any disks in any order with New Config. If you assign any disk to any parity slot, that disk will be overwritten with parity.

 

Nothing else about any of your settings are affected.

[MegaMustang]

ok 1 last question. I really appreciate your help. if i want all my pools i setup , as far as what goes to the cache drive and what stays on my array data drives only would you recommend  "Preserve current assignments:" and hitting all?  

[trurl]

After you apply New Config, you get the Main page with the array stopped and then you can make any changes before starting the array.

 

Preserve all is the simplest because then it will remember the current assignments. Then you can go from there to change them as you want before starting the array.