Possible having 4-Drive-bay with only 2 drives, so later add another 2 drives preserving data


Is it possible to have a 4-Drive-bay like the DL4100/EX4100/EX4, with only 2 identical hard drives, and two empty spaces. So in the future add another 2 identical hard drives for expansion preserving the data of first 2 drives. If yes, can the second pair be of different capacity. Can the 4 drives act as one RAID, or it must be set as two RAIDs to preserve data.


I don’t know about the EX, but I would bet it was similar.  I have the DL4100 and you can do pretty much anything you want

I think it will migrate from raid 1 to raid 5 with no data loss, but it has been a while since I played with it. In any event you should always have a backup of your data.

Say you have two, 2tb drives raid 1 with a 2tb capacity.  You add a 3tb drive and migrate to raid 5, you will have 4tb useable.  The new drives must be as big or bigger, but it can only raid the capcity of the smallest drive.


DL4100 with 2 drives, does it make a difference (pros/cons) having them as RAID1 or RAID5?

If later 1 extra drive is added, are there pros/cons from RAID1 or RAID5 to RAID5?

I’m considering the DL4100 with 2x6TB RAID5. Then add one 6TB when needed. Then add another 6TB when needed. Could there be any issues or data loss when adding extra drives?



You can only have raid 0 (no data protection) or raid 1 (2 drives mirrored) with two drives.  Raid 5 requires 3 or more drives.

As I said I am fairly certain it will migrate from 2 drive raid one to 3 drive raid 5

Even if I said I am positive it will migrate from 2 drives raid 1 to 3 drives raid 5, you should have a backup of your data unless it is something you don’t really mind if it gets lost.


Thanks for the info. RAID1 it is with 2 drives.

A friend of mine, Christopher Lloyd, helped me travel to the future where we were able to successfully migrate from RAID1 (2 Drives) to RAID5 (3 Drives) in less than 5 hours. We also tested the following with the DL4100:

Activity                       Duration (hh:mm:ss)
Single Disk Init                         00:09:06
JBOD to RAID-1 Migration                 08:37:27
RAID-1 (2D) to RAID-5 (3D) Migration     04:43:33
RAID-5 (3D) to RAID-5 (4D) Expansion     18:01:04
RAID-5 (4D) Rebuild                      08:50:33

Actually Copy/Paste the above from:

Final thought, will buy DL4100 with 2-6TB, then add 6TB as required.

Thanks for your help, there goes 1/10 of a keychain.