Given the specifics, this setup makes me nervous.
Now let me explain:
Pictures:
RAID 0 isn't the safest thing for primary data, but can be acceptable if you've a proper backup solution (not just a source for it, but the interval they're made). The reason is, there's going to be some data lost if you were working on something when it failed (time between last backup completed and the array failure). This can be acceptable if you've the time to deal with fixing the array, restoring the data you have on the backups, and re-performing the lost work.
Where the problem is for me, is that you're backup solutions are software based RAID 5. Since the data is written in this case far more than it will be read, you run the risk of that data being corrupted during a write. This will render the data useless to you, and a significant loss. Not acceptable to my way of thinking (I think of the R in RAID, which means Redundant). A level 5 in it's basic premise is redundant, but it's not secure enough when done by a software implementation.
That's what I was getting at with the Highpoint 2314. You can reduce this risk with a good UPS system (MP, monitor, and both PM enclosures; you should be running one for the Areca anyway). But it's still not as secure as the Areca you have would be (since it contains an NVRAM solution to the write hole issue).
With the new 2TB drives I've installed I have the space to put 'Pictures' on the Areca array so it sounds like I should do that.
Video:
This seems fine, but what are the particulars?
- Model of Areca card
- Enclosures used and cabling (particularly the drive count)
It's a 1680x Areca with a ProAvio 8MS enclosure with two mini-SAS cables.
http://www.proavio.com/eb8ms_specifications.html
I'm running it with 8 Hitachi 2TB Deskstar drives.
I ask, as I'm wondering if the Areca could be better utilized (i.e. run a separate SATA array in level 5 for the Primary if there's sufficient ports, or possibly via SAS expanders <they will run SATA disks as well>), and change the PM enclosures to a JBOD configuration.
Please note, that with the Areca, the drives must be enterprise models for the recovery timings (consumer units are set at 0,0 and enterprise at 0,7 <read/write respectively, and values are in seconds>).
I know the drives aren't enterprise class but the only 2TB drives with consistent good ratings for RAID are these and their enterprise cousins. Many people claim to have had good results building RAIDS with them and one of the best RAID vendors in the UK uses them (Rent-a-RAID). The enterprise version was more than double the price. How much of an issue do you think the recovery timing thing will be?
Backups:
You need to get these swapped out of a software implementation of level 5, as the write hole issue nullifies the presumed redundancy. Corrupted data is useless, so why make sure the corruption survives if a disk dies?
You'd be best served IMO by a JBOD configuration, as the risk is that of a single disk. The "downside" is it also has the performance of a single disk, so the time needed to complete the backup will be increased. But as speed isn't the primary concern here, it's an acceptable trade-off for your needs.
This is the primary problem with your setup as I see it. If you change this over, your primary arrays will have sufficient protection. But not as your backup is currently configured.
What's the deal with recovery from a failed drive in a JBOD set-up?
BTW, what's the OS location?
Separate drive with the applications in the Mac Pro. I'm considering getting an SSD.
See above.
RAID 5 is fine for reads. But its the writes that's the danger. Since the primary usage of the backup system is to write data to it, your risk is higher than other forms (1/10/JBOD) that corruption will occur during a backup process.
Unfortunately, you won't know it either, and won't discover it until you've had a catastrophic failure of one of the primary arrays, and restore the data. At that point, it's too late. Some or all of the data is garbage = gone.
But the Highpoint software can be set up to check parity. Something I've not done but I guess ought to do.
I'm under the impression you've a second copy (duplicate it to each PM enclosure), and you're betting on the fact that the same data won't be corrupted twice over. Better than a single source under certain conditions (backups run separately). But if both backups are written simultaneously (which can be set in backup software I'm familiar with), it will be duplicated.
Quite an ugly situation to find yourself in.