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zoran

macrumors 601
Original poster
Jun 30, 2005
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Hi, i would like some advice on how would you believe is the best way to use a HDDbay (OWC Mercury Elite Pro Qx2) in order to keep a backup of my files that are located in multiple devices…
- iMac (mid2010) that has two drives on it (one SSD that contains the OS and apps and one HDD)
- iPhone
- iPad
- a HDD with files
- an external HDD
The OWC bay can take up to 4HDD and is also capable of utilising RAID
Please note that i certainly would like to be using Timemachine!
I would really appreciate to reading your suggestions :)
 
With you OWC bay connected, it can be selected as the Time Machine destination. Other external drives can be added to the list of drives to back up in System Preferences --> TimeMachine->Options and remove the external drives. All drives must be formatted HFS+, the standard Mac OS format. If you back up you iPhone and iPad to the iMac using iTunes then Time Machine will back up those backups as well. It's a good idea to use all encrypted drives.

Using RAID will add little to your backup security. You will have no protection against theft, fire, or natural disasters, or even a failure of you backup (IMHO Time Machine is convenient but not reliable). For best protection you need at least one off-site backup and multiple backup approaches. I use TimeMachine, cloned disk backups (two sets, alternating, with one always off-site), and a cloud backup (Crashplan). I've used all of these for recovery.
 
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That drive bay will connect via USB or Firewire, so it can naturally be a time Machine target.

TM on your iMac will backup anything on the SSD (unless specifically excluded) as well as content on the second (internal) HDD. Just make sure the HDD is not specifically excluded in the Time Machine options. However, I don't think (I could be wrong on this) the external USB drive content will be backed up, so simply copy that data to the OWC array every so often to have a backup copy of that content. See below for backup of data on the array.

If the question is how to setup RAID on the bay, that is a wide open one. With all 4 drives in a RAID5 configuration, you would see the bay as a single drive of size N-1. In RAID10, you would effectively see 50% of the total raw capacity.

So, if there are 4 2TB drives, the capacity would be 6TB in RAID5, and 4TB in RAID10.

RAID10 is a bit faster, but with USB2 or Firewire 800, the connection will probably be the bottleneck rather than the drives.

All of the data on these drives would be "backed up" by virtue of the RAID. In the event of a drive failure, you replace the failed drive and the controller re-constructs the data that was on the failed drive using the data\parity info on the remaining drives. So, no need to do extra backups of this, unless you are super sensitive to data loss. RAID10 is resilient if more than 1 drive fails, RAID5 only allows reconstructing the data if 1 drive fails.

I believe you can partition the array using Disk Utility, so you could use a 1TB partition for Time Machine and the balance for data.
 
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Just a pointer; if you use iCloud, make sure you have "Optimize Storage" off in Photos, and "Optimize Mac Storage" off in iCloud Drive options. This will ensure that all your iCloud data is stored locally on your Mac, and backed up with Time Machine.

Then if something gets deleted/corrupted in iCloud, you can go back to an earlier backup and restore it.
 
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Guys thanks for all the answers, may i ask if it is possible to backup iPhone/iPad to a specific path of my choice and not the OSX drive which happens to be the SSD? I dont want to have any files other than system and app files on it.
 
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Hi, i would like some advice on how would you believe is the best way to use a HDDbay (OWC Mercury Elite Pro Qx2) in order to keep a backup of my files that are located in multiple devices…
- iMac (mid2010) that has two drives on it (one SSD that contains the OS and apps and one HDD)
- iPhone
- iPad
- a HDD with files
- an external HDD
The OWC bay can take up to 4HDD and is also capable of utilising RAID
Please note that i certainly would like to be using Timemachine!
I would really appreciate to reading your suggestions :)
I've moved away from local backups. Hurricanes, fires, theft, ect can ruin a day. I currently use iCloud to backup everything. All devices automatically sync documents. If the worst happens and a fire, tornado or lightning destroys my property, all I have to do is order new stuff from Apple. Log into my iCloud account and everything is safe and sound. No lost pictures, source code, projects, notes, even remembers where I last was streaming an iTunes movie. Plus it is built into the products. No extra steps.
 
Guys thanks for all the answers, may i ask if it is possible to backup iPhone/iPad to a specific path of my choice and not the OSX drive which happens to be the SSD? I dont want to have any files other than system and app files on it.

iOS device backup choices are iTunes on the local Mac\PC or iCloud. If you backup to iTunes on Mac, your backups will be stored in ~/Library/Application Support/MobileSync/Backup/somelonghexfoldername. It is unfortunate that this is hard coded, even if you relocate the media folder in Advanced Preferences.

But, alas, there is a way...though not for the light hearted. You need to create a symlink to a folder on the non-boot drive to trick iTunes into storing the backups on the other drive. The following articles explains the steps in pretty good detail. Mind you, this is not an advised method, but the article does have the undue steps if you run into problems.

http://www.imore.com/how-move-your-iphone-or-ipad-backups-external-hard-drive

The drive you move these to can be either internal or external, the point is the link needs to accurately point to the correct location where you want to store the backups. Another word of caution... if you will be storing these on external drives that can easily be lost or stolen, by all means use encrypted backups. If someone gets the drive with your iOS backups without a password, they would have the keys to the kingdom.
 
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Thanks techwarrior, what i want to do with the iPhone and iPad backups, is to move them to the internal 2nd drive i have on my iMac. I dont want backups or files i dont use on my SSD, purely because i prefer not to fill the fastest drive with stuff like that, i prefer to have it for my everyday use procedures (working with apps etc.).
You think its a good idea?
 
Thanks techwarrior, what i want to do with the iPhone and iPad backups, is to move them to the internal 2nd drive i have on my iMac. I dont want backups or files i dont use on my SSD, purely because i prefer not to fill the fastest drive with stuff like that, i prefer to have it for my everyday use procedures (working with apps etc.).
You think its a good idea?

Good idea? No... anytime you have to resort to "hacks" you are subjecting yourself to complications. Viable, certainly.

The bigger question is, how much space do your iOS backups consume, and is that a deal breaker for your SSD. I have a 128GB iPhone, and 64GB iPad. Combined backups consume about 12GB of space on my boot drive.

You may be obsessing over this, if drive capacity is that much of a concern, it might be time to consider a larger SSD or creating a Fusion partition.

If you combine the SSD and HDD into a single volume, macOS will manage where to store the files, in effect, implementing your strategy "auto-magically". You benefit from a single drive with combined capacity of the two drives, fast access to the stuff you use, and no need to sweat the small stuff. So, while 99% of your "documents" may be accessed on rare occasions and thus storing them on HDD makes sense, the 1% that you use often would also be slowed, with Fusion, macOS would store the 1% on the SSD for faster access. Same with Apps, the rarely used apps would move to the HDD.

Creating a Fusion drive is not too complicated, but it is destructive. So, do a full backup, then proceed, then restore.

There are a lot of guides on how to create your own Fusion drive, this one preserves the Recovery Partition:
http://hints.macworld.com/article.php?story=2014030311173257
 
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Personally I would set the OWC up as a JBOD. On my 5 bay JBOD I use:

1. Drives 1 & 2 (6 TB each) for 2 Time Machine Backups. Backed up to alternate disks each hour. Ideally use same size disks (helps in setting TM backup options) from different vendors (extra protection from simultaneous failures).
2. Drive 3 (2 TB) has 2 1 TB partitions. These are used for Carbon Copy Cloner clones of my boot 1 TB Disk every other day
3. Drives 4 & 5 are backups of directories of directories that aren't changed that often and that are so large that they would fill my time machine backups, such as pictures. I also don't backup Parallels as the data for the apps I use there (e.g. Quicken) is backed up to my boot drive so if it fails I just reinstall Windows. No need to backup the whole virtual machine.

I would recommend having 2 TM backups. Years ago I went to do a restore and the TM backup although seeming to be OK was actually corrupt and unusable. Just this last week my "Put hard disks to sleep when possible" setting in System Preferences - Energy Saver somehow got toggled to on. This resulted in my 2 TM disks to be unexpectedly ejected and TM couldn't fix one. I tried to rebuild it with Disk Warrior but there were over 100,000 files that couldn't be salvaged so I had to reformat and start TM over from scratch. Then a few days later they other TM also became unusable and so it had to be reformatted as well.

I found one old report of unexpected ejects occurring with the (OWC Mercury Elite Pro Qx2).
 
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Hmm regarding the fusion drive although it might seem to be a good solution i gotta admit that it feels like uncharted territory for me, so i may leave it to be my second option. My first might be to purchase another 4TB HHD, place it in the OWCbay and do a TimeMachine backup of the SSD . Then install El Capitan on the SSD, and restore some of the files from the TMbackup. (i guess it is possible to restore selected files from the TMbackup of older versions, like Yosemite right?).
And then use that 4TB as a 2nd TMbackup drive (HDFan did alarm me by saying that he has come across faulty TMbackups, maybe having a second one can be safe... huh?).

What do you think of my thought? I haven't decided yet for anything, im just thinking out loud here!
 
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I built a Fusion on a Mac Pro 2008 with Mavericks as i recall. It has performed flawlessly and got me around the small 120GB SSD limitations. In all, the boot drive was about 1TB and I didn't need to move much content to other drives (I have close to 1TB of Video\Music in iTunes, so I did keep that on extra HDD in the Mac Pro.

The creation of Fusion takes a bit of care, but follow the directions and you will be OK. I know several people who have gone this route without issue, and they were not particularly savvy users. You can pair the SSD (any size) with HDD (any size). You get the full benefit of SSD for boot speed and App loading, but also get the extra storage from the HDD without having to mess around with changing paths. Despite it being destructive (both drives will be reformatted in the process), it is well documented and works quite well.

Your TM backups can be of any (recent) version as long as it is older than, or equal to the target system.

I am a little uncertain about restoring 2 drives to 1 if you go the Fusion route, I suspect Migration Assistant would import only the user data that was on the old SSD, then you would have to go into Time Machine and Restore the data that was on the HDD to the new Fusion drive. Presumably you didn't move the entire home directory to HDD?

You might read over this site for some tips, http://pondini.org/OSX/SetupOther.html, this site covers a lot of Time Machine topics. If your entire home folder was moved to the HDD, you might have to move it back to the SSD (along with the ~/Library folder), do another backup, then migrate. The contents of the documents, iTunes media etc would still be on the HDD, but you could then restore the HDD contents back to the Fusion drive after the migration is complete. Or, you might talk to an Apple Store Genius to get their advice.

Dual TM backups is not a bad idea. I use Airport Time Capsule alone, and have had no issues through two restores, but if your content is critical, by all means take the extra precautions. I have also done several restores from USB backups without issue.

One more word on the OWC. JBOD is fine for creating tons of storage space, but RAID gives you resiliency. JBOD is just like attaching a bunch of USB drives, any one can fail and you lose the data (unless backed up), but RAID uses parity (or mirrored images depending on which RAID level you choose) so a drive failure simply requires you to replace a drive and the controller will restore the data. In RAID5 or 10 with the 4 drives, you can get a massive amount of capacity with resiliency and dual TM backups will not be critical as the RAID will in effect create the resiliency. However, the whole thing is subject to catastrophic loss (fire, flood, theft), so an additional backup offsite is the answer if you want total peace of mind.
 
In RAID5 or 10 with the 4 drives, you can get a massive amount of capacity with resiliency and dual TM backups will not be critical as the RAID will in effect create the resiliency.

True, you're not as subject to failures via hardware failure. But you are still subject to corruption. My problems almost always come after unexpected ejects, or if a backup to a Time Capsule or a write to a disk hangs. If you never get those then I wouldn't worry as much. Sudden ejects on non-TM drives don't tend to be catastrophic. Someone pointed out the article

http://basilsalad.com/how-to/time-machine-wireless-backup/

"Then there are the problems of the virtual disk’s book-keeping information (filesystem data structure) that may not get written correctly in addition to the data itself. What’s worse is that if the file system information gets corrupted during a write operation, the entire disk’s integrity may be compromised."

"Time Machine needs this because it uses a special HFS+ feature called directory hard links at the heart of its operation."

If you lose a block of data on a file then that's just one block which needs to be recovered. But if you lose a block of links then you are losing not just a block from a file, but you're losing all of the files linked to in the block. The files may still be there, but without the links they are lost. But this is just a guess. Maybe someone else has more information.
 
Suppose i do the fusion drive option and one of the two drives gets damaged... either the SSD or the HDD, what happens with my TM backup, how do i make restoration and where?
 
Suppose i do the fusion drive option and one of the two drives gets damaged... either the SSD or the HDD, what happens with my TM backup, how do i make restoration and where?
Once you got it fixed you would restore from TM just as if you had a single drive. TM sees the Fusion drive as one, virtual drive.

So you could option key boot to the TM disk, use Terminal and Disk Util to format and rebuild your Fusion drive with the new disk, then restore.
 
Ok, so correct me if im wrong, im always referring to my case (iMac with 2 drives, ssd & hdd). Ill have to replace the faulty drive (either SSD or HDD), make a new fusion drive out of the new "duet" and then restore there.
For my case, i will always have to create a fusion drive to restore, simply because the drives used, will always be more than the max my mid 2010 corei7 iMac can handle. Im no sure if i can install more than a 1TB HDD on my iMac... can i?
 
Ok, so correct me if im wrong, im always referring to my case (iMac with 2 drives, ssd & hdd). Ill have to replace the faulty drive (either SSD or HDD), make a new fusion drive out of the new "duet" and then restore there.

Correct... you've got it.

For my case, i will always have to create a fusion drive to restore, simply because the drives used, will always be more than the max my mid 2010 corei7 iMac can handle. Im no sure if i can install more than a 1TB HDD on my iMac... can i?

Sure you can swap out to a larger hard drive then make a Fusion drive out of that.
 
How can i know what is the largest HDD drive i can install on my mid2010 corei7 iMac?
 
I see OWC is selling up to 6TB drives, so I'm assuming that would work fine.

SATA III is the key, just about any size will work, the OS X drive size limit is about 8 EB (ExaBytes), but practically, single SATA II drives max out in the 6-8TB range.

And, yes to the process described above to rebuild, not so unlike rebuilding with a single drive failure, just add the Fusion step which only takes a couple of minutes.

You can have a max of 2 drives in that iMac.
 
what do you mean by that?

Follow the steps in my post here.
[doublepost=1493817921][/doublepost]
SATA III is the key, just about any size will work, the OS X drive size limit is about 8 EB (ExaBytes), but practically, single SATA II drives max out in the 6-8TB range.

I know newer Macs are like you described, but I recall some of the older ones the logic board could not see more than 3TB, so I was searching around to make sure I was correct for OP's 2010 model.
 
If I decide to create a fusion drive, is there only one way to create it? Or are there more than one ways?
 
If I decide to create a fusion drive, is there only one way to create it? Or are there more than one ways?

To my knowledge, the only way is via Terminal commands at the recovery partition. I assume the GUI Disk Utility does not support this because they want us to buy Fusion drives from the factory and pay the Apple Tax.

Follow the guide noted above, but make sure you clearly understand the restore options if you are currently spanning multiple drives with your backups.
 
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