Need help. Is EX4's RAID 1 a RAID 1 or a RAID 01?

I recently purchased a second-hand EX4, and installed 4x 4TB Seagate Ironwolf disks in it. I selected to format it as a RAID 1, and was expecting to get one volume of 4TB of storage, with a fault tolerance of 3 disks. What I got instead was two volumes of 4TB each, with a total storage of 8TB.

This does not seem to be a true RAID 1 configuration. This seems to be either a RAID 01, or a RAID 10. Since there is already a RAID 10 option, I reckon it is a RAID 01. But in no way can this be a true RAID 1.

Please correct me if I’m wrong, as it seems that I can only be either very correct, or I can be very confused.


All 4-Bay Personal Cloud, Network Attached Storage devices come pre-configured with RAID 5 by default.

Please refer to this KB article for more information: How to Change the RAID Mode on a RAID Enabled My Cloud Device

Hi, and thank you for your reply. Unfortunately I don’t see how this is related to the original question. I did not buy mine new; I bought it used and it came disk free. The four Seagate disks I installed myself, and they were brand new. No RAID configuration was pre-selected in my case, nor did I have any difficulty switching between RAID configs. My question has to do with the possibility that the RAID 1 that results from formatting the four drives that way seems more like a RAID 01, and I need to verify whether that is the case, or if I am being very wrong with what my expectations should be.

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