Any reason I cannot replace Parity Drives and Empty Data Drives at the same time?


mikesp18

3 posts in this topic Last Reply

Recommended Posts

I'm upgrading.  Final goal removing 2x older Data drives (already emptied 4TB drives), shifting 2x 10TB drives from Parity drives over to Data drives, and adding in 2x new 14TB Parity Drives.

 

I'm removed all the data from both of the data drives already.

 

What is the most efficient order of operations here?  I've done this in the past when adding 2x new Parity drives into the array and shifting existing parity to data drives, but this takes a very long time.  Is there something I'm missing? I'm just wondering if there is a more efficient way to do it than I have done in the past.

 

2nd question, can a drive be pre-cleared/cleared in one Unraid installation and then moved over to another completely different Unraid installation?  Or does the clear/pre-clear operation need to be done on the same machine the drive is being installed into?

Link to post
1 hour ago, mikesp18 said:

2nd question, can a drive be pre-cleared/cleared in one Unraid installation and then moved over to another completely different Unraid installation?  Or does the clear/pre-clear operation need to be done on the same machine the drive is being installed into?

This question has been asked here many times. It can be done on a separate machine.

Link to post

Assuming you aren't concerned about maintaining at least single parity during all this.

 

If you are rebuilding both parities anyway, you can just New Config and assign any disks to any slots, regardless of what is on them or whether they are cleared or formatted. Parities will be calculated based on the bits of all data disks and so will be valid for whatever is on the disks.

 

Any disk assigned to a parity slot will be completely overwritten with parity, and any disk assigned to a data slot will not be changed. Any that have a mountable Unraid filesystem on them will be mounted. If you want, you can format those, and format any that don't mount.

 

Parity will be maintained if you format any data disks, and in fact, parity will be updated as needed even during parity rebuild so those bits of it remain valid when you format or otherwise begin using the data disks.

 

You already got your answer on preclear, but just thought I would add that preclear isn't necessary, but many use it to test new disks.

 

There is only one scenario where Unraid requires a clear disk. That one scenario is when adding a data disk to a new data slot in an array that already has valid parity. This is so parity remains valid, since a clear disk is all zeros and so has no effect on existing parity. In that one scenario where Unraid requires a clear disk, it will clear the disk if it hasn't been precleared.

Link to post

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.