EX4100: JBOD to RAID migration



I am considering buying an EX4100. One of its features that caught my eye is the RAID migration feature, which allegedly allows one to transform a bunch of disks into a RAID array. But I am reading conflicting information on the issue:

Except the linked KB page (ID: 17305) clearly states on step 7: “Changing the RAID mode will erase all of the data on the drives listed below”.

Also, this thread (Can't add drive without deleting data) asking the same questions about migration went unanswered.

The product manual (4779-705140.pdf) in chapter 9 says the same: the operation will erase all data.

Then it shouldn’t be called “migration” IMHO :).

So can we or can we not move from JBOD to RAID-5 WITHOUT data loss?

My use case:

I have 2x 4TB WD disks with data on them. I am planning on buying the EX4100 with 2x more 4TB red disks. I am thinking of plugging the 4 into the EX4100 and make it one big RAID-5 volume, while keeping the data I have in my current 2x 4TB disks.

Question 1: if I add 2x NTFS disks with content when initializing the EX4100, will they retain their data or will the device reformat them? I suppose it will reformat them to ext4, and them I’ll lose the data? Or can it migrate from NTFS to ext4 without data loss.

Question 2: now suppose I have 2x 4TB disks in JBOD with data, either copied onto them or migrated from NTFS hopefully. If I add 2x empty 4TB disks, will I be able to actually migrate the 4 disks into a RAID-5 array, WITHOUT DATA LOSS?

Question 3: How will the RAID-5 be formatted? One single large volume/file system? Can I map it onto for instance disk z: on my windows 10 PC? Or can I make multiple volumes, and also map them as disks z: and y: ?

Thank you.


Hi host2626,

If you are using 2x 4TB in RAID 1 configuration then only you would be able to migrate it to RAID 5 without data loss.

Please refer to the link given below for more information.