Importing Disks with Data

[Richman]

I was reading over the manual and I wanted to confirm that I read it correctly. First let me relate what my intention is. I was planning on setting up 3 x 1TB disks of which I already have in a NTFS stripe or JBOD array initially until I get my (4) 3 TB disks to set up a ZFS pool and then migratete data over to the ZFS pool. To set up the initial (3) 1TB disks, the manual talks about importing disks that are already formated to a certain FS, namely NTFS and doesn't mention data being on them or not. Sound to me that they can be imported with existing data as long as you don't reformat them again. The way I understand it is it will stripe to the other disks, or mirror the data if that is what you set up.
Am I correct in my understanding of what I read?

 

[Dusan]

FreeNAS can import individual NTFS formatted drives so that you can copy data of them. However, it will not put it into a stripe/JBOD -- you need to access/share every drive separately. Also, if your NTFS drives are already striped then you won't be able to import them at all.

 

[Richman]

FreeNAS can import individual NTFS formatted drives so that you can copy data of them. However, it will not put it into a stripe/JBOD -- you need to access/share every drive separately. Also, if your NTFS drives are already striped then you won't be able to import them at all.

Nothing is striped . So what you are saying is, you can import an NTFS formatted drives into Free NAS but you cannot import it directly into a ZFS pool you are creating with DATA already on the drive Even though you are keeping the same NTFS format in your RAID array ?

 

[cyberjock]

"import it directly into a ZFS pool"? What is that even supposed to mean!?

You need to go read up on NTFS and ZFS more!

 

[Richman]

I think Dusan knows what I'm talking about. That means I have 3 x 1 TB disks with the data on them formatted NTFS . The Manual implies that I can build my first NAS box and create my first array with these disks without reformatting or deleting the data . Or maybe they can't be technically an array and would have to be single disks. They would not have to be in an array necessarily . But I was wondering if they can be imported into a newly created JBOD, or a mirror if I were to add 3 more 1TB the disks.

 

[gpsguy]

What Dusan told you was that "FreeNAS can import individual NTFS formatted drives so that you can copy data off them."

When *you* set up your array, you'll need to have disks that are blank. You can use either UFS or ZFS for the filesystem. Having setup this new array, you can copy the data from your NTFS disks and remove them from the box. Some folks find it safer to just copy the files over the network from a Windows machine to FreeNAS.

Down the road, imagine that your motherboard died. At that point, you could import your UFS/ZFS array into a new machine without reformatting or deleting the data.

 

[Richman]

What Dusan told you was that "FreeNAS can import individual NTFS formatted drives so that you can copy data off them."

When *you* set up your array, you'll need to have disks that are blank. You can use either UFS or ZFS for the filesystem. Having setup this new array, you can copy the data from your NTFS disks and remove them from the box. Some folks find it safer to just copy the files over the network from a Windows machine to FreeNAS.

Down the road, imagine that your motherboard died. At that point, you could import your UFS/ZFS array into a new machine without reformatting or deleting the data.

I fully understand what Dusan was saying.
So, ie: Even if one has data on a UFS formatted drive(s), you cannot create a mirror array and have the system copy the data to the mirrored disks. Disks always have to be empty when adding them. Correct?
If this is correct it was not clear in what I read in the Manual. Maybe it could be reworded better.

Don't understand why it can't be possible. UFS is just the file system. The software raid system should be able to set up a simple mirror and copied data to that mirrored disks since the disks are already in the format you're going to use and they don't have to be reformatted.

 

[Dusan]

Disks always have to be empty when adding them. Correct?.

No, you can import disks containing data. You can import:

• existing ZFS pools
• UFS single disks
• UFS graid3
• UFS gmirror
• FAT & NTFS single disks (importing means that the drive will be mounted and the data can be accessed, nothing more)

However, you can't use imported UFS or NTFS drives to create mirrors and magically preserve the data.
If you want to create new gmirror/graid3/raidz/... configurations you need to use empty disks (any data on the disks will be lost).

Don't understand why it can't be possible. UFS is just the file system. The software raid system should be able to set up a simple mirror and copied data to that mirrored disks since the disks are already in the format you're going to use and they don't have to be reformatted.

It doesn't work that way. Even the simple gmirror ("the UFS mirror") needs to store its metadata somewhere (the mirror configuration). You have to first create a gmirror, it will store the metadata on the disks and only then you can create an UFS filesystem on the mirror. It doesn't work the other way around. You can't take an existing UFS drive and say hey you are now part of a mirror please sync your data to that other drive.

 

[Richman]

No, you can import disks containing data.

That was my initial plan anyway. I just wanted to make sure noting further was in FreeNAS ability or in the works. I was thinking what they used to import disks w/data if you an only read and write to them just as in a share but then, I guess there are other benefits, like being able to access them remotely and have all of your data in one box.