Is this possible?

Luke284

Luke284

Luke284

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I have two 500Gb drives and I want to be able to "see" them as a single 1tb drive. I know I could use RAID 0, but then if one drive dies I lose all the data. Is there another way? so if one drive dies I only lose half the data?

thanks
 
Luke284 said:
I have two 500Gb drives and I want to be able to "see" them as a single 1tb drive. I know I could use RAID 0, but then if one drive dies I lose all the data. Is there another way? so if one drive dies I only lose half the data?

thanks
Click to expand...

JBOD is what you're looking for.. it's another kind of raid, and stands for Just a Bunch Of Disks. It will most likely be an option in the raid bios setup.
 
ah, ok. I'll have a look into that. its quite an old mobo, so im not holding my breath.

with JBOD if i take one of the drives out and plug it in to a sata port elsewhere what will happen? is there anyway of seeing what is on each physical disk?
 
ok, thanks. I'll look into that. I've already got data on the disks, if i convert them into a spanned volume am I likly to lose my data? What happens to the spanned volume when i format the system drive?
 
Luke284 said:
ah, ok. I'll have a look into that. its quite an old mobo, so im not holding my breath.

with JBOD if i take one of the drives out and plug it in to a sata port elsewhere what will happen? is there anyway of seeing what is on each physical disk?
Click to expand...

JBOD would present a single drive to the OS so no, the RAID BIOS won't have that information and I'd doubt that the raid utility would either.
With a spanned volume in Windows there should be a way, I'm quite positive of that.
 
Luke284 said:
ok, thanks. I'll look into that. I've already got data on the disks, if i convert them into a spanned volume am I likly to lose my data? What happens to the spanned volume when i format the system drive?
Click to expand...

I know you can convert a basic disk to a dynamic disk but I don't know if the spanning is non-destructive, I don't see why it wouldn't be.. As to the second question, that information is stored on the drives so nothing would happen.
 
doesnt look like JBOD is supported on my motherboard (ASUS P4C800-E DLX) looks like I will have to go down the dynamic disk route.
 
after having a little play around, it looks like I have to delete the current volumes to create a spanned volume so would involve losing the data stored... Looks like I might have to find some extra hard drives as temp storage, or just get a 1tb disk!
 
I understand that using dynamic spanned disks gives the same issue of losing all data if one drive fails. If it's not too late, and if you're currently using NTFS, you can have one disk volume appearing as subdirectory of another (have a look at Computer Management/Disk Management, Change Drive Letters and Paths). All without having to reformat, but I'd make sure you have a good backup anyway!
HTH
 
i always keep the same amount of disk space free as my largest drive incase i need to recover it.

with JBOD, unless you have it in an external case that supports it on board, you cant remove one disc and be able to read it on another as the partition is still accross the 2 discs. as far as i know you can recover data from 1 drive if the other fails
 
it's safer to keep them as 2x 500gb drives imo

what i sometimes do is create a shortcut from one drive to another, so it creates the 'illusion' of a folder :p
 
what happens if the drive mounted as a folder is an external one? will it work the same as normal. i.e. turn it on the folder appears?

also could you move it to a different pc?
 
lopkinfop said:
what happens if the drive mounted as a folder is an external one? will it work the same as normal. i.e. turn it on the folder appears?

also could you move it to a different pc?
Click to expand...
The drive just contains an NTFS formatted volume, whether it's external or internal, mounted at a folder or as a drive letter is irrelevant. The host system just deals with it wherever in the filesystem it's put.
 
Yep,

Best safe option where the disks can be used independently if required would be to mount one drive on the folder of another.

Open computer management;
[START] -> [Right Click] "My Computer" -> [Left Click] "Manage".

Select Disk Management.

Mount the drive;
[Right click] the partition you wish to mount in the bottom right pane.
[Left Click] "Change Drive Letter and Paths.."
You can now either add a new mounting;
[Left Click] "Add"
[Left Click] "Browse" and navigate to the folder you wish to mount the partition on (folder must be empty).
The partition will now be accessible as both the original drive letter and through the folder you mounted it on.
Or you can make it the only mounting by deleting the drive letter;
[Left Click] to select drive letter.
[Left Click] "Change"
[Left Click] "Browse" and navigate to the folder you wish to mount the partition on (folder must be empty). --I am guessing this part as this work machine only has one drive / partition and so I cannot change the C: assignment as it is the boot partition.

This should be fine for Windows XP. I do not use Vista so have no idea if the method is the same or if they have funked it up a bit.

Mounting Partitions on one another.

Upside;
Volumes are completely independent and so can be split without data loss or any special recovery.

Downside;
No backup unless one volume is being used to backup the second.
Moving a file over to the other partition via the mount point is the same as moving the file between the two drives so takes longer than moving a file within the same partition where only the FAT for the partition gets amended.
Each partition is still limited to the individual drive size. If the mounted partition is 60GB and you fill it up then you cannot write any more data there even if there is space free on the 'host' partition.

Spanning / JBOD.

Upside;
Volumes are seamlessly combined so look like one big disk and share IIRC one FAT. Moving files around is quicker than mounting. Copying takes the same time as a physical copy of the data is still required.

Downside;
No backup.
Failure of one drive makes recovery of the second drives data more difficult.

RB
 
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