How do I "Expand Capacity" on my EX4100?

I started with the EX4100 (24TB) kit.
I had the typical drive failure due to the inferior standard 6TB drives provided with the unit.
I received the replacement and instead wanted to expand capacity with the 10TB drives so installed this. The RAID5 was rebuilt, but is missing some capacity and now have the remaining 4TB un-allocated currently. How do I add this into the RAID5 I have currently?.
What are the ACTUAL steps for doing this? I have not been able to find a step-by-step instruction on how to “Expand Capacity” of my RAID5. It seems like it wants to go through and force me to replace drives instead of just allowing me to allocate the remaining empty partition of the 10TB drive to be included in the current RAID5 designation.

Is there a standard process?
The ‘Search’ function is less than adequate here and does not return what I search for.

The closest I found was this thread depicting some steps, except I have already installed the 10TB drive.
o If I run this, remove the 10TB drive, and then just put it back in, will it reallocate or not?
o If I run this, will I have to replace all drives to redefine the RAID5?
o Is there an actual document that depicts this, or any, method involved based on my current RAID configuration and an already instilled drive? (This would be really nice to have WD!!, because there is NOTHING in the User Manual about this function and “Product Features” is a dead link.).

Thanks for help/advice/etc.

Hi offroadace,

You have setup the RAID5 on your device and your My Cloud enclosure have 3 * 6TB and one 10TB drive setup.

Due to RAID setup on your device, your device is able to rebuild the RAID with only 6TB partition on the 10TB drive and leaving the remaining 4TB space on the drive as un-allocated which cannot be used in anyway.

You can use the full storage of all the drives by using the JBOD setup on your My Cloud device.

Thanks. I have been finding more info on RAID5 and that it is a limitation of the software. Some allow different drive speeds and sizes, but the size is a limitation.

Do you know of a process that would allow for an upgrade of all 4 drives to 10TB?

If I replace the current drives 1 by 1 then the partition will remain at 6TB. How would I define them as 10TB?
Would I need to offload the data externally and then build the entire NAS with 10TB allocation?

Why have an Expand Capacity on RAID5 if you can’t actually do it?

Ho offroadace,

Did you ever get an answer for this? I’m imagining that if you replaced all the other drives 1 by 1, then you would be able to use the Expand Capacity option, but that’s only a guess.

In any case, I’m in the same boat and would like to upgrade my disks in order to expand the size of my RAID volume, but I’ve noticed there is an incredible lack of information and/or response on this topic. It doesn’t seem to be something anyone at WD has considered, which doesn’t really seem possible??

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Hey dabber86.

Well, no, not really. Just trail and error,…mostly error due to lack of consistent information from WD about the topic and less than adequate resources or reference material.

Here is what I found, during my trial and error period and online research, unrelated to WD support;
You CANNOT have different sized drives for the Expand process on the WD NAS, when using RAID5 like I am. Possibly this will work with other RAID or general drive configuration or other NAS OS’s.

If you have 4 drives at a 2TB capacity in RAID5 and you intend to expand capacity, [ALL] drives MUST be replaced. If you go to 4TB, you need 4 drives at 4TB capacity otherwise the Expand process with continually “not complete” indicating to replace the “Next” drive. Not very informative either, but based on information available regarding WD NAS OS level questions, not surprising.

If you have 2x 2TB drives in a 4bay NAS you could most likely just add another 2TB drive to expand to 6TB with an open drive. But then you aren’t using RAID5 as it requires 3 drives to begin with so it will be a general expansion and possibly allow for RAID5 afterwards (if all derive capacities are the same I imagine)…

If you are using RAID5 - ALL drives must match capacity (from what I have found). I have not seen a clear statement on this, just again, through trial and error and the actual Expand process not completing and indicating to ‘Replace Next Drive’.

So, to summarize, if you have a 4bay NAS with all matching drives and intend to expand to a larger capacity, while maintaining RAID5, you MUST swap ALL drives to the intended target capacity. In my case I started with 4x6TB drives and expanded to 4x10TB drives. Expand does not allow mismatched capacities in RAID5 on WD NAS (from what I have found). You might be able to do this on other NAS devices or through other NAS OS, just not through WD NAS OS, but not according to support because that was not clearly stated anywhere by anyone.

There may be other variables involved but I am not a network/system Admin and like it when things are made easy so I can enjoy life.

Good luck.

Just to reiterate - RAID5 - ALL DRIVES MUST MATCH!!! :wink:

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I agree, all drives must match. If you replace 4 2TB drives 1 at a time, it can only rebuild at the smallest drive size, which would be 2 TB. I don’t think there is a way to expand the array once you replace and rebuild all drives in the RAID5 (I don’t think it is smart enough, like a true hardware RAID controller). So, it would be backup the data, replace all drives, CREATE A NEW ARRAY, and then restore the data. I’m in the same boat, I just had 1 drive in a SMART failure so I need to replace them soon. I do backup the data to an external drive, so I have that going for me.