Another newbie with two Thunderbay 4

I can configure CCC to backup only half a volume?

Yes you can!

In CCC, you select the volume target in the "Source" window.
then in the pulldown select "Copy Some Files". Then uncheck a couple folders.

A simplistic way to describe this is arrange the files in your RAID volume structure to top level folders, A and B.
then in CCC, for one source, uncheck B, in the other Source, uncheck A.

then CCC will skip the B files on the first Clone process, and skip the A files on the second. All you need to do is keep the total size of files in each folder somewhat balanced.

You need to select the disks.

Be sure you disable safeguard on the volume, then you can certify. We have a setup video on Certifying Disks on the web site that you can refer to.

Note: Any pre-populated Thunderbay from OWC comes with disks that have been certified!

You need to select the disks.

Be sure you disable safeguard on the volume, then you can certify. We have a setup video on Certifying Disks on the web site that you can refer to.

Note: Any pre-populated Thunderbay from OWC comes with disks that have been certified!

Be careful with that assumption. I bought a 16TB ThunderBay 4 and Slot A was bad in the chassis. I didn't certify them and had data corruption. The disk in slot A failed certification and so did a replacement drive until OWC replaced the chassis.

Me again. So now I'm using CCC to backup my 24TB and 12TB RAID 5 volumes to the two old 5 bay USB enclosures that I was using before SR/TB. That means I have 2 4x4TB TB4s 'spare'. I'm thinking of making them into a 2 enclosure 1+0 RAID.

Alternatively, I want external backup to my Synology DS416 play NAS with a 4x4TB SHR volume. I'm about to get an external 8TB drive from OWC, but was wondering if I could use a SR volume? I'm assuming that it's a 'no' - you would need the SR drivers to recognize the volume?

Alternatively, I want external backup to my Synology DS416 play NAS with a 4x4TB SHR volume.

This phrase is a little confusing, but I am guessing you want to ask if you can use the Synology as part of your SoftRAID volume?

As you guess, no, in that only "direct attached" devices can be used by SoftRAID. They need to be controlled by Mac OS, not by the operating system inside the enclosure.

No, I want to use my SR volume in a TB4 enclosure with the NAS but you answered the question anyway. And plus there isn't a TB port on the NAS so the whole thing is moot. Thanks.

So yesterday one of my 4TB disks in my 4x4TB RAID 5 was marked for replacement. I swapped it out and after 12 hours the RAID is back up with no problems, which is a big difference from the last time a drive failed in my USB rack. Good stuff.

One thing though, was that the Softraid software flashed up a message saying that a write error was detected on the disk, and it stalled my whole system. I had to restart (a couple of times). That surprised me a bit - I thought that an error in an external disk shouldn't freeze the whole system, but no biggee.

An error "should not" hang an entire system, but can. SATA spec says a disk that encounters a problem can time out for up to two minutes while it works on it (retries, reallocate sectors, etc.)

OS X will likely hang if the drive pauses, without responding for longer than a few seconds. More likely that is what was happening.

An error "should not" hang an entire system, but can. SATA spec says a disk that encounters a problem can time out for up to two minutes while it works on it (retries, reallocate sectors, etc.)

OS X will likely hang if the drive pauses, without responding for longer than a few seconds. More likely that is what was happening.

Thanks. I had another drive fail on a RAID 5 and getting it up and running was very painless. If I have 4 thunderbay (TB2 versions) - currently only using 2 daisy chained to one port on my MBP 2015. I have two old 5 drive USB enclosures that I use Carbon copy to 'backup' the stuff on the TBs.

I'm thinking that I should probably let my USB enclosures go and make use of the other two TBs (bought in a fit of panic with my big drive fail disaster). I would then have 4 TBs. I'm guessing the whole system would work better on say a 2013 Mac Pro, with each TB having it's own port. Or would it not make much difference?

Cheers

The Thunderbay enclosures should work faster and better. USB is not ideal for RAID 5.

there are three buses on the Mac Pro. But with HDD's, you need three on a bus to see any speed limitations. So daisy chaining a pair of enclosures is not an issue.

Thanks. I'm not using the USB for RAID, I'm using them as standalone drives and using CC to copy certain directories to the drives. The USB is housing mostly older drives that I've had before.

So would it be a bit silly to get a Mac Pro 2013 primarily for the thunderbolt ports?

Yes.

LOL, thanks.