ReadyNAS Pro 4 - HDD Upgrade

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MikeDold wrote:

Hello
im am using a ReadyNAS Pro 4.
Im planning to upgrade the 4 HDDs. The RAIDiator Version is 4.2.31.
What is the maximum size of HDD, i can use in this (old) NAS?
One of the HDDs is broken, so i changed it with a WD RED 4TB - the funktion is ok, but the HDD is shown as 1863 GB HDD.
So i am in trouble to upgrade all of the HDDs and the NAS cant use more than 2TB...

thanks for your answers

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4,2,31 systems can use larger disks than 2 TB.  But you need to install two larger disks to see any expansion.  The XRAID capacity rule is "sum the disks and subtract the largest".

There are two expansion limits with your firmware.

• The NAS cannot expand to a volume size over 16 TiB
• The NAS cannot expand more then 8 TiB from the volume's starting size.

If you started with 4x2TB drives in place, your NAS started with a 6 TB (5.4 TiB) volume.  Upgrading to 4x4TB would work in this case, since you'd end up at 12 TB - well under the 8 TiB expansion limit.

Buf if you started with just a single 2 TB disk in place, you'd have had an initial volume size of only 2 TB.  Your expansion would fail in that case.  If this is your situation, you'd need to do a factory default, and rebuild the NAS.  Then reconfigure it, and restore the files from a backup.  You should consider converting the NAS to run OS-6, as it doesn't have any known expansion limits.  However, that would also require rebuilding the NAS and restoring the files from backup.

If you aren't sure (likely it was some years ago), then you might as well try expanding it, and see if it fails at some point.  Then do the factory default.  I strongly recommend making a full backup first, as expanding all the disks does put some stress on the system.

Though you didn't ask for advice on disks, I do recommend NAS-purposed or enterprise class disks.  However I don't recommend using the WD40EFAX, as it uses SMR technology.  Either go with the Seagate Ironwolf, or see if you can get an older WD40EFRX model.

Note you could also get to 12 TB by upgrading two drives to 8 TB - which has a similar cost.  If you went that route, the WD80EFAX would be fine (it is not SMR).