Replace Parity and change file system on Data drives to XFS

[zaniix]

I have searched around a bit and I think I know what I need to do, but I am hoping some of you that are more experienced could chime in if my plan seems stupid.

Current setup
uRaid 6.8.3
One Parity Drive  3TB
two Data drives each 3TB   - formated ResierFS
new drive not installed yet 4TB

 

End goal
1) new 4TB drive as Parity
2) old Parity drive as Data Drive formated XFS
3) all data drives reformatted to XFS

4) end result one new 4TB parity and Three 3TB data drives

I realize this is multiple processes, but I am want to make sure I am doing this in the most efficient and safe manner
with the least risk to my data.

 

My Plan
1) add new drive as unassigned and preclear just to make sure it is safe to use
2) stop all backups to unRaid, shut all VMs and Docker images.
3) turn off auto start, shutdown remove old parity drive
4) boot add new drive to parity slot, start array, wait for parity rebuild

5) shutdown and connect old parity drive, add as data drive, add exclusion to all shares for this drive to prevent any data being written t it
start array, format XFS
  following this process  https://wiki.unraid.net/File_System_Conversion#Mirroring_procedure_to_convert_drives 
  
 in short copying data to empty drive and then swapping positions and format and restarting array each time.

6) restart any VMs, Dockers, and backup jobs

7) backup flash drive config

 

 

I know this topic has been covered a lot, but there is always a detail or two that I find unclear so I appreciate any help.

[trurl]

2 hours ago, zaniix said:

4) boot add new drive to parity slot, start array, wait for parity rebuild

5) shutdown and connect old parity drive, add as data drive, add exclusion to all shares for this drive to prevent any data being written t it

If you do these as 2 separate steps, then you will have to let Unraid clear the "new" data disk so parity remains valid.

 

If instead you New Config, assign new parity to parity slot and old parity to new data slot, then when parity rebuilds everything will already be in sync and you can just format "new" data disk.

 

Rest of your plan sounds good.

[zaniix]

1 hour ago, trurl said:

If you do these as 2 separate steps, then you will have to let Unraid clear the "new" data disk so parity remains valid.

 

If instead you New Config, assign new parity to parity slot and old parity to new data slot, then when parity rebuilds everything will already be in sync and you can just format "new" data disk.

 

Rest of your plan sounds good.

So are you saying that I should move the unassigned drive to the parity slot and the old parity drive to a data drive slot and do a copy parity?

then start array and format?

 

 

 

 

[trurl]

New Config lets you change your disk assignments however you want, then optionally (by default) rebuilds parity. That is all it does. Some people seem to be afraid of it thinking it will reset everything. Just make sure you don't assign any disk with data on it to any parity slot.

1. Go to Settings - Disk Settings and make sure Default file system is XFS.
2. Stop the array.
3. Go to Tools - New Config, keep all assignments. It will let you change them however you want before starting the array.
4. Assign new disk to parity slot, old parity to new data slot, leave all other assignments the same.
5. Start the array but DON'T check the box that says parity is valid, because you (obviously) need to build parity.
6. When parity build completes, format "new" data disk.

Since parity will be built with the "new" disk already in the array, everything will be in sync.

 

Then format just writes an empty filesystem to that new disk. (That is all "format" does, many people are very confused about that). An empty filesystem is just the filesystem metadata needed, some of which represents an empty top level folder ready for new folders and files.

 

Format won't take very long because it doesn't have much to write. Since Unraid treats that write operation just as it does any other, by updating parity, everything is still in sync.

 

Result is new parity and new empty XFS disk ready to hold the data from another disk so you can format it.

 

[zaniix]

8 minutes ago, trurl said:

New Config lets you change your disk assignments however you want, then optionally (by default) rebuilds parity. That is all it does. Some people seem to be afraid of it thinking it will reset everything. Just make sure you don't assign any disk with data on it to any parity slot.

1. Go to Settings - Disk Settings and make sure Default file system is XFS.
2. Stop the array.
3. Go to Tools - New Config, keep all assignments. It will let you change them however you want before starting the array.
4. Assign new disk to parity slot, old parity to new data slot, leave all other assignments the same.
5. Start the array but DON'T check the box that says parity is valid, because you (obviously) need to build parity.
6. When parity build completes, format "new" data disk.

Since parity will be built with the "new" disk already in the array, everything will be in sync.

 

Then format just writes an empty filesystem to that new disk. (That is all "format" does, many people are very confused about that). An empty filesystem is just the filesystem metadata needed, some of which represents an empty top level folder ready for new folders and files.

 

Format won't take very long because it doesn't have much to write. Since Unraid treats that write operation just as it does any other, by updating parity, everything is still in sync.

 

Result is new parity and new empty XFS disk ready to hold the data from another disk so you can format it.

 

Thank you, that clears that part up.  I just know how easy it can be to forget a small detail and destroy all the data.