Replacing 2Tb Seagate Hdd with 3/4 Tb Disks

The procedure is to do a backup, then remove one of the disks, and insert the new one with the NAS running. Wait for the resync to totally complete before moving to the second. The backup is an important step, as the RAID array has no redundancy while the expansion is in progress.

There are two expansion limits - the first the NAS will not expand to more than 16 TiB. If you need more than that, you will need to do a factory reset with all storage in place, and restore the data from backup.

The second limit is that the NAS will not expand a volume more than 8 TiB from the starting point. If you did your initial install with 6x2TB all in place, then you will reach the 16 TiB limit first.

Follow up questions please:

I also have readynas pro rndp600 with 6 WD Blk Cav 2tb disks.

If I decide to upgrade to the WD red 3tb and replace them one at a time, will I start to see the expansion right after the first drive completes?

Or after the 4th?

Going to the 3tb, =18tb, but after system stuff would be 16-17tb, so with the limitation discussed above, I'd end up with 16tb, which is not far off. Is that correct thinking?

Thanks in advance.
Steve

Are you using single or dual-redundancy?

Using single you would need two disks replaced before expansion can commence. Replace one disk, wait for resync to complete then replace the next one.

Using dual-redundancy four disks need to replace.

As a very rough calculation (6-1)*0.9*3 < 16. So even using single-redundancy you would have to use 4TB (or greater capacity) drives to hit the 16 TiB limit.

Wow, thanks much for the prompt reply!

I'm only single, but would like to go dual redundancy.

Now makes me think the best bang for my buck would be a clean load of 6x4tb drives.

1) back up my 9.2 tb NAS
2) pull my 6 x 2tb drives out.
3) put in 6 x 4tb drives and config for dual redundancy
4) restore my NAS backups to the fresh installed ReadyNAS Pro

questions:
How much space will I have with 6 x 4tb drives with dual? and how much if I just keep it single?
When do I config the dual, after adding the 4th drive?

Thank you so much!

Dual would give you about 3.6 TiB less than using single.

As a very rough calculation (6-2)*0.9*4 or look at the volume size calculator link in my sig.

When you do a factory default with four or more disks in place you could open RAIDar and during the 10 minute countdown click setup and choose X-RAID2, tick the dual-redundancy option and confirm your choice.

THanks again!

So based on calculations and using 4tb drives, single=18tb and dual=14.4tb.

1) would I even need to do a fresh install from scratch? or is that needed to get to dual mode only?

My bottom line questions:

Is there a difference in final size for adding the 6x4tb drives one at a time into the exiting system?
or is there a space advantage be regenerating from scratch and keeping single mode?

My guess is I would have to gen from scratch to convert to dual mode?

Many thanks!

There are two growth limits:
(a) You can not grow a volume beyond 16 TiB. But you can do a factory reset, and create a volume that is bigger than 16 TiB.
(b) You cannot grow a volume more than 8 TiB larger than its starting point.

Whether you go single or dual redundancy, you will need to do a factory reset/start from scratch - because with single redundancy you'd exceed the 16 TiB volume limit.

Also, because of the limits, you don't want to install 1 drive at a time.
For single redundancy, insert all 6 drives.
For dual redundancy, insert 5 drives. After the volume is formatted, add the sixth drive for redundancy.

Aw....all clear now, thanks for putting up with all my questions!!!!

I know what I need to do now, thanks so much.

Best regards....

Camelxx, you mentioned the 3TB WD Red drives in an earlier post, then you began asking about 4TB drives but did not specify a model.

The 3TB Red drives (model WD30EFRX) apparently work fine, but the 4TB Red drives (model WD40EFRX) have a problem at the moment that makes them unsuitable for use in a ReadyNAS Pro. If you want 4TB drives, I would suggest choosing another model unless you can confirm that the problem with the Red drives has been fixed.

Problem details are here: https://www.readynas.com/forum/viewtopic.php?f=24&t=73417

Thanks, I did look at drive compatibility first and saw the Hitachi 7k4000. I was actually wonder if WD red 4tb was okay. Thanks for the heads up.

Guess it's only the Hitachi for now.

Cheers.