Another newbie with two Thunderbay 4

SoftRAID does not care what is inside a volume, rebuilds are the same and the time to rebuild is the same, as the entire volume has to be made identical on each disk.

I was giving the Apple recommendation for volumes, as the HFS file system is not good at managing full volumes.

A Softraid volume (RAID 5) which is currently empty is now reported to have a disk that has failure predicted. This drive was certified just a few months ago, and has not been written to since, but now apparently there are 8 unreliable sectors. I'm assuming that the drive manufacturer (Toshiba) will only accept dead drives rather than dying drives?

Sijnce this is showing "unreliable", rather than "reallocated", what you need to do is certify the disk again. (3 pass). This could have happened from a brown out, power surge, etc, or the drive failing. Certify will either result in the disk showing OK, or the disk will reallocate the sectors, in which case we recommend replacing it.

If you bought the disk with your Thunderbay from OWC, they will let you replace the drives.

Okay thanks. So I certified again. It passed but reallocated 1 sector. I bought the disks from a local supplier, not OWC.

this drive is on a failure path then. I recommend trying to get it replaced. It may work for a while for consumer purposes, but for important data, I would not trust it, it will fail sooner rather than later, most likely.

Drives are sold untested, which is why a certify is important, it tells you immediately whether a disk can be used reliably "out of the shoot".

So I bought some 8TB HDDs from OWC during their last sale. Just finished certification.

Obviously the RAID 5 is going to be big, 24TB. I'm going to copy over the data from my other two 4x4TB TB4's onto this. What would be the best way to back up this 24TB volume please?

One way is to keep backing up to your older RAID volumes.

Blackblaze is good, but you can imagine how long it takes to back up that much data on line. They used to have a policy where you could ship them the drives, not sure if that is still available.

Or, when you get the budget, get another set of those drives and back up to another 24TB volume!

good thing you realize a RAID volume is not the same as backup!

Thanks. I have backblaze for the internal SSD of my MBP, it's too slow for these softraid volumes.

Quick question. You don't subdivide volumes right? You just use it as one big volume with your directories and subdirectories?

I have CCC, so is there a function to backup a larger volume onto smaller volumes/ disks or is it manual copying?

SoftRAID allows you to create as many volumes as you want. You are not restricted to a large RAID 5 "LUN", which you create volumes on, you can create a RAID 5 volume, a RAID 0 volume, and Mirror volumes on the same disks, for example.

Most users just create a single volume. However, many users will create (example) a RAID 0 volume for scratch work, then a RAID 5 volume for storing data, etc.

Once a volume is created, we do not "partition" the volume. What you do is either:
delete the volume and create the specific volumes and sizes you want.
We also support resizing the last volume on a set of disks so you can take an existing RAID 5 volume, shrink it, then create a new volume with the free space now available.

Wait. So I can make my TB4 with 4 x 8TB drives into 2 x12 TB Raid 5 volumes?

Another scenario, the 2 TB4s with 4x4TB that I had and copied data over to a third TB4 with 4c8TB drives - I can make a big Raid 5 with the 8x 4TB drives over 2 enclosures?

yes you can.

yes. SoftRAID makes no limits on the types of RAID volumes, or sizes, when you are creating volumes.

The only real limit is all partitions of all volumes be the same (which SoftRAID auto-enforces). So you cannot create a volume with a 4TB 4TB 4TB and 6TB partition, the last partition will be 4TB also. 2TB will remain for additional volumes if desired.

Thanks. So what's more sensible, split the 4x8TB 24TB RAID 5 into 2x12TB volumes and then clone each of these to one of the 4x4TB RAID 5
or
make the 2 4x4TB enclosures into one 24TB RAID 5 that backs up the current 4x8TB?

Or should I look at nonRAID drives/ volumes for backup? This is where I was looking for software that would span drives. It seems to exist for Windows but not OSX.

What is wrong with leaving a 24TB volume and just configuring your backup software to do half of the volume to each 12TB smaller volume? Its simpler.

I would recommend 4 drive volumes, rather than 8 drive volumes, though.

whatever works for you would be fine.