Is this possible/sensible?  I currently have all my array drives set to BTRFS for the extra features like scrub (which I use) and snapshot (which I don't), but I'd like to try XFS on at least some of the drives, since it's supposedly quite a bit faster.

Do I need to use the standard procedure for file system conversion here, or can I get by with just moving the data to another drive, reformatting the now empty drive with XFS, and then.....?  Do I need to rebuild parity, or create a new config, or...?

Thanks for any pointers.

Unraid does not care what mix of file system types you use as each disk is a self-contained file system.

48 minutes ago, servidude said:

or can I get by with just moving the data to another drive, reformatting the now empty drive with XFS, and then.....?  Do I need to rebuild parity, or create a new config, or...?

The sequence of events is:

•  Empty the drive by copying its data elsewhere
• Stop the array
• Click on the drive on the Main tab and change the file system to the one you want.
• Start the array - the drive will show as unmountable
• Use the option to format unmountable drive on the Main tab.   Make sure it is the drive you expect as the format erases the current contents and creates an empty file system of the desired type.

Parity is maintained throughout as parity is file system agnostic and just sees a format as another write operation.

3 hours ago, itimpi said:

The sequence of events is:

• Empty the drive by copying its data elsewhere
• Stop the array
• Click on the drive on the Main tab and change the file system to the one you want.
• Start the array - the drive will show as unmountable
• Use the option to format unmountable drive on the Main tab.   Make sure it is the drive you expect as the format erases the current contents and creates an empty file system of the desired type.

Thank you for this @itimpi!  So the final step would then be, copy the data back to the new drive (with its new files system)?

5 hours ago, servidude said:

Thank you for this @itimpi!  So the final step would then be, copy the data back to the new drive (with its new files system)?

Yes, assuming that is where you want the data to finally reside.