I have an old StarTech NAS box containing two 2TB Caviar Green (WD20EARS-00MVWB0) (RAID 1) supporting my Windows 10 Laptop and a separate 500GB WD caviar Blue (WD5000AAKS-00A7B0) i a WD “My Passport” supporting a MacBook via Time Machine. I am looking to migrate to a WD NAS box and am considering the 2-bay Mycloud devices.
Though five-years old - the Greens are only powered up once a week for the backup (any intermediate backups done by copying to thumb-drive) and so probably have a fair bit of life left in them.
One option is to procure a populated device (Red drives) and then just copy across - possibly keeping the third-party NAS as an extension so as not to waste those Greens.
Another option is to procure a four-bay - with two Reds and the two Greens - but that has an extra cost while being excellent for expansion.
The third - and cheaper option - is to procure an empty device and use the Greens. But how? Do I break the current RAID, move the “spare” Green (Disk B) into the WD (does it keep its data?), then move the second Green (A) across and rebuild the RAID using the old B as primary?
I have sufficient spare capacity on the Greens to be able to set up a share for the Mac and could then use the Blue as a portable backup device.
Comments? I am starting to favour the first option if I can afford it.
Your only choice is to copy the data. The WD won’t understand the formatting or partitioning of any other vendor’s NAS.
If youor current NAS is RAID 1, you could, in theory, get a 2-bay empty NAS.
Pull one drive from the current NAS (making the RAID1 degraded, but still functional).
Wipe that one drive, install it in the WD and make a NEW RAID1, but with only one drive. ---- that’s a wildcard, though, because I don’t know if the WD will allow the creation of a RAID without all members present.
At any rate, if it does, then copy the data over, then pull the 2nd drive, wipe it, and install it into the WD RAID set.
Many thanks. I have just bought an empty 4-bay so as to give me room. But that doesn’t resolve my issue. Your suggestion sounds eminently sensible but - as you say - relies on the ability of the NAS to accept a RAID with just one disk.
Can it accept one in a JBOD - copy the files across - add the second disk and convert to RAID?
I will see how much of my data is actually needed as I do have about 500GB of storage available elsewhere in bits and pieces - including an old Laptop drive with an adapter (can’t remember the size).
I also have some old SATA disks from old PCs in a cardboard box somewhere. Most of these will be small - but I may find one or two of a reasonable size. One/two could be added to the 4-bay as JBOD - copy the files across - take the two 2TB Greens - add them to the NAS box - format - RAID - copy the files across.
I need to delve into cardboard boxes looking to see what drives I can use to store the data while I create the RAID.
My shopping list will be for some larger Reds - but that will need to wait a few months.
Thank you again.
Just to finish this off.
I backed up the RAID1 on the original NAS - removed the two 2T Greens and inserted them in the EX4100. I didn’t know that the EX4100 could accept a third-party RAID set (nothing in the documentation I could find) and so instructed the device to create a RAID1. It successfully tested the two drives, partitioned and formatted - but failed to create the RAD volume. I contacted support who asked for screen shots which I have sent.
In the mean time I noticed that there was a firmware upgrade available. But I couldn’t install it. Again the documentation was not helpful - but this forum said I needed a disk to enable the upgrade. So I created a JBOD volume and it worked. I upgraded the firmware.
I then created a RAID0 and this also worked. So I tried RAID1 again and it failed.
Then I decided to try creating the RAID1 while not using all the capacity of the disks. So I took 10GB off and it worked.
I have informed the support desk and am waiting for the response. In the mean time I am using the RAID1 with no issues.
I think it would have worked if you’d wiped the partition table from the drive before starting the install process, but not sure since I’ve never attempted that. 
