Raid5 Array Size Upgrade?

[cafords]

Other than a full backup and restore, is it possible to upgrade a raid5 array from:
4 x 1tb to 4 x 2tb?

Everything I have read indicates this is not possible.

I actually have already hotswapped all 4 drives with a rebuild for each, however, the physical size of the array remains 3tb. The additional capacity is not recognized in setup.

Thank you for your comments.

[yohojones]

I dont think its possible. Special raid devices like the drobo can do this but a raid 5 has to be copied off, rebuilt with the new disks and copied back.

[ajamison]

There is a 1 drive failure rate with RAID 5 you can use this to your advantage, pull one drive out (after making a backup of all data) and then mount your new drive. This drive will be used to repair the array but will only allow you to use 1TB of space since the other drives are 1TB. Once the rebuild is complete remove another 1TB drive replace it with an 2TB drive let it rebuild and then repeat.


Once all 4 drives have been replaced you may need to extend your RAID volume to take up the additional space. It is important to not remove more then 1 drive at a time.

I realize this topic is over 8 months old but I answered it so that future users might benefit from this. As with anything this is not without some aspect of risk which is why backing up is important. It will also take alot of time because you have to rebuild the Array 4 times (each time a new drive is added).