I have a new 4TB which I will be using as a cache disk and warm spare in the near future. Due to an ongoing parity rebuild and data recovery effort, it is currently formatted to NTFS, and has some backups of backups. I will keep them on that disk until I have re-built parity and ran a parity check. After this I would run pre-clear and set it (again) as cache.

 

Can I set the drive as cache, and move files from the disk to the array? Or do I need to re-format it and lose data? This would save me one array reset and opening up the box to put in the drive.

I have a new 4TB which I will be using as a cache disk and warm spare in the near future. Due to an ongoing parity rebuild and data recovery effort, it is currently formatted to NTFS, and has some backups of backups. I will keep them on that disk until I have re-built parity and ran a parity check. After this I would run pre-clear and set it (again) as cache.

 

Can I set the drive as cache, and move files from the disk to the array? Or do I need to re-format it and lose data? This would save me one array reset and opening up the box to put in the drive.

I am not quite sure what question you are asking? 

 

I THINK it is whether setting the 4TB NTFS formatted disk that already has data as a cache disk will lose its current contents?  If so the answer is yes so you first need to move any data already on it that you want to keep to another location.

 

You mention an extra 'case opening'!  Is there any reason you cannot start without a cache disk but install the 4TB NTFS disk that is intended to end up as cache.  When the data has been moved off it you can (optionally) pre_clear it and then allocate it as the cache disk.

I THINK it is whether setting the 4TB NTFS formatted disk that already has data as a cache disk will lose its current contents?  If so the answer is yes so you first need to move any data already on it that you want to keep to another location.

 

 

The question is in the subject. Thanks, that answers it!

 

You mention an extra 'case opening'!  Is there any reason you cannot start without a cache disk but install the 4TB NTFS disk that is intended to end up as cache.  When the data has been moved off it you can (optionally) pre_clear it and then allocate it as the cache disk.

 

No other reason than laziness

You mention an extra 'case opening'!  Is there any reason you cannot start without a cache disk but install the 4TB NTFS disk that is intended to end up as cache.  When the data has been moved off it you can (optionally) pre_clear it and then allocate it as the cache disk.

 

No other reason than laziness

That reply makes me think communication has not occurred. You can physically mount the disk in the slot that will eventually be assigned to cache duties but leave it unassigned in the unraid array drive list, and use the ntfs add-on package to read the contents of the disk and copy it to the array. After that is complete, you can assign it as cache, and unraid will offer to format it for you to use as a cache drive. Only 1 case opening required.

 

Or did I misread the situation?

The simple answer to your question is NO.

 

But as Jonathan noted, you can mount the drive externally (to the array -- not to the physical PC) and copy the data using the NTFS add-on package;  copy the data to your array; CONFIRM that it's there; and then Stop the array and assign the drive as your cache ... this will result in it being reformatted and a subsequent loss of any data already on it.

 

Personally, I'd just leave the NTFS drive in your Windows system (I assume that's where it is at the moment) ... copy all the data to your UnRAID server across the network;  and THEN move the drive to the server and assign it as the cache drive.

 

But either approach will work just fine.

 

Thanks. Due to the error-prone and complex add-on installation, I decided against even trying that, and left it in my desktop until I'm done with re-building the array.