Adding a 4th drive to EX4100 Raid 5

EX4100 with three 4TB drives in RAID5 configuration. If I add a fourth drive, will the RAID rebuild itself across the four drives and bump up from 8TB to 12TB capacity? Expanding the capacity under the same raid level without losing data in the process??

Haven’t been able to find a clear answer to the question. There’s an option in the setup for “Auto Rebuild” when adding or removing a drive which I would assume has to be turned on, but it doesn’t answer the core question of whether adding a fourth drive results in an new, expanded RAID5.

Thanks in advance for your replies,
VictorZ

Hello,

You might be able to do that using the option to change to RAID 5 and select the option to create spare disk, this will add the new drive without rebuilding the RAID.

Thank you for your reply. It’s not that I’m concerned about rebuilding. If it can accept the fourth disk, add it to the total space available to the (existing) RAID 5 array, I would expect it to require rebuilding. My question regards whether this process … expanding the existing RAID 5 capacity … can be accomplished without data loss.

Worst case in my opinion is that the data would need to be offloaded and a new array set up from scratch, then copy the data back on. That would be a pain. While the current 8Tb capacity is not full, it would still be a long and fraught process to do it without losing or corrupting something.

VictorZ

I am now in this same situation, three 4TB drives and need to add a fourth. Did you ever find out if this could be done without data loss? I’m not sure if I could even find space to offload my data if expanding the raid can’t be done without a full wipe.

I’m also worried about the same thing.
I have 3 x 4 TB storage and it’s almost full. It is configured as RAID 5.
I need to add a 4th drive and expand my RAID 5 without losing data. I don’t think I can backup the whole data and built the whole thing from scratch again. [quote=“VictorZ, post:1, topic:160862, full:true”]
EX4100 with three 4TB drives in RAID5 configuration. If I add a fourth drive, will the RAID rebuild itself across the four drives and bump up from 8TB to 12TB capacity? Expanding the capacity under the same raid level without losing data in the process??

Haven’t been able to find a clear answer to the question. There’s an option in the setup for “Auto Rebuild” when adding or removing a drive which I would assume has to be turned on, but it doesn’t answer the core question of whether adding a fourth drive results in an new, expanded RAID5.

Thanks in advance for your replies,
VictorZ
[/quote]

Is there any possible way to do it ?

You should definitely have backups of anything critical or irreplaceable … but in fact, I was able to add the drive and expand the storage capacity with no problem. It DID take a long time to complete the process. but the end result was a seamless expansion of total storage capacity.

1 Like

Thank you very much for the reply.
@dswv42 @VictorZ can you tell me where do you find that migrate option?
I’m already on RAID 5 and need to add more drive. I couldn’t find any option to do so.
Please advice.

hi
i know this is an old thread but recently i have been facing a related issue. i had 3 x 6TB hard drives running in EX4100 on RAID 5 configuration. i added a fourth drive in it and selected to expand the storage capacity through the UI. the process started normally and smoothly till it reached 34% in one day. Now, for the last 3 days it is stuck at 34% with fan rpm at 600. the data isnt accessible (understandable), but even the mycloud UI is not accessible through the browser. I havent tried putting it off because i guess it may affect the hard drives if i switch it off. Desperately need help to come out of this situation. I dont care about the data already on the storage. Just need it to be up and running. Thanks

What was your end result? I am in the process of setting up my EX4100 with 3 x 6TB drives and hope that I can add a 4th drive as-and-when I need in the future. If it’s likely to fail then perhaps I should bite the bullet and get the 4th drive now.

I had a similar requirement which was to change my two 3TB drives in my EX2 to two 6TB drives. Admittedly, I am using RAID 1 which is slightly different. Naively I thought I could just add one 6TB drive first, wait for it to be rebuilt and then replace the second 3TB drive with my second 6TB drive and all would be done.

It didn’t work and frankly the support here from WD techs was useless.

In the end as I had the data elsewhere (photographs) I just wiped everything clean and re-copied over the data. It took me a day but at least I now have my 6TB RAID 1 configuration.

Personally, I think this is a poor support from WD and they need to create much more usable information about this process - even if it is just to set expectations that you cannot easily expand the memory of 2-drive, or even 4-drive devices.

I surely hope someone gets an answer to this query. I backed up my network to a 4TB drive. Now that my EX4100 in up & running I want to move the files from the backup to the EX and use the HDD as my 4th drive.
I’ll be most displeased if there is no way to do this.

I’m on the same situation as pretty much everyone here, need to add a 4th disk to an existing RAID5 setup without data loss and I am wondering if this is possible?

I added a 4th drive with no real issues. The only thing that ■■■■■ is it will take a long time for it to rebuild the raid. When I added a 4th 3TB drive it took like a full day before it was up and running again.

1 Like