(SOLVED) Reduce the number of parity drive from 2 to 1

[kinaley]

Hello friends,

Still fiddling around with the magical unRAID O.S.

I have 6 disks and have configured the disk as below

2-parity disk

3-data disk

1-Cache disk

Everything is running good without any issue.

I just want to reduce my number of parity disk from -2 to 1 and add the 1 disk from parity to data disk and make 4 - data disk in total.

(without losing data , is that possible ?)

attached is the snapshot of my current disk configurations.

Thanks

 

Edited April 5, 2019 by kinaley
Solved

[kinaley]

I thought I found the information on wiki pages https://wiki.unraid.net/UnRAID_6/Storage_Management#Assigning_storage_devices but no it doesn't mention about the reducing parity disk from 2 to 1.

waiting for some wise people to guide me.

[JorgeB]

Stop array

Unassign parity2

Start array

Stop array

Re-assign old parity as data disk

Start array to begin clearing the new disk

[kinaley]

12 Hrs 😞 ,

There is option like Quick Format or Full Format while formatting drives.

I know it sounds silly and might not exist

is there such option as Quick Parity Start and Full Parity Start.

Anyways Thankyou johnnie.black

[JorgeB]

Clear needs to write the full disk, no quick option, but you can use the array normally during the process, unlike before v6.2, also 12H is too long for a 2TB disk, make sure write cache is enable, some SAS devices come with disabled.

 

[kinaley]

Thankyou so much that really did the trick.

Installed the nerdpack gui plugin as it was saying sdparm command not found.

invoked the commands

To set the write speed

sdparm --set=WCE /dev/sdb
sdparm --set=WCE /dev/sdc
sdparm --set=WCE /dev/sdd
sdparm --set=WCE /dev/sde
sdparm --set=WCE /dev/sdf
sdparm --set=WCE /dev/sdg

and Verified with
sdparm -g WCE /dev/sdb
sdparm -g WCE /dev/sdc
sdparm -g WCE /dev/sdd
sdparm -g WCE /dev/sde
sdparm -g WCE /dev/sdf
sdparm -g WCE /dev/sdg

NOTE: didn't had to reboot.

and the result is attached from 12 Hrs to 3hrs.

That was awesome. Thankyou for saving 9Hrs of my time.

Many Many Thanks

 

[kAI53r]

I have a slightly different problem:

 

I just added a bigger parity 2 drive and want do remove the parity 1 drive aferwards.

 

My setup loks like this:

 

parity 1 : 4tb

parity 2: 6tb

 

disk 1 : 3tb

disk 2 : 3tb

disk 3 : 1tb

 

Here is what I would like to do:

1. remove parity 1

2. stop + start array

3. stop array + switch make party 2 to parity + start array again

4. afterward I would like to put the 4tb drive on disk 1 position and move all disks in the array one postion down. --> Herefore I do not know how to proceed.

 

Why I want to do this?

- because the is the best way for me to spread data across the array using relative methodes on the different shares like "high-water" (for larger files like movies) "filling-up" (like system/unraid files, the have mteh alls on the same drive)

- there is no need to use set up operations that will send the data to preselected disks.

 

Did you do something simelar, I am looking forward hearing from you.

 

 

 

[itimpi]

You can skip step 2 and do both step 1 and step 3 at the same time.    This will then rebuild parity1  Your array is unprotected until that finishes so keep the old parity1 intact until that completes in case something goes wrong while rebuilding parity1.

 

Note that once you have a valid parity1 you can reorder disks without affecting parity (would not have been true for parity2)..  The way to proceed would be:

1. Use Tools->New Config (i would recommend you use the option to preserve current assignments to reduce the chance of error).
2. Go to Main tab and move all existing disks down a slot, and at the end leave disk1 slot empty
3. Tick box that says parity is valid and start array to commit assignments.   You can ignore a warning about parity being over-written as the check box stops that happening
4. Stop array and assign old parity1 as disk1.
5. Start array to commit this change.   Unraid will start a 'Clear' on disk1 to avoid it affecting parity.   When that completes you can format disk1 to make it ready for use.

[kAI53r]

thank you very much.

 

Just to understand what is happening in the backround:

 

If I would have a pairty 1 and a parity 2.

 

Is it possible to remove parity disk 1 and put parity disk 2 into the parity 1 position.

 

Would this cause any error or lead to an unprotected parity? Do any parity rebuilds or so be the result of this?

[itimpi]

1 minute ago, kAI53r said:

thank you very much.

 

Just to understand what is happening in the backround:

 

If I would have a pairty 1 and a parity 2.

 

Is it possible to remove parity disk 1 and put parity disk 2 into the parity 1 position.

 

Would this cause any error or lead to an unprotected parity? Do any parity rebuilds or so be the result of this?

If you do that you need to rebuild parity as parity1 uses a different algorithm to parity2.

[kAI53r]

3 minutes ago, itimpi said:

If you do that you need to rebuild parity as parity1 uses a different algorithm to parity2.

ok, now I get it.

 

TY