I'd like to experiment connecting multiple drives to a Mac Mini (late 2012) model with a suitable SATA adapter. From what I have read, the SATA controller needs to supports port multipliers for this. Does this Mac Mini model have a SATA controller with the port multiplier feature? System report in SATA / SATA express section says it has "*Intel 7 series*" chipset.

I was wondering if MacOS Mojave (the most recent version I can be on due to some very expensive 32 bit applications) has a way to set up a system level "virtual" dir, or virtual drive, that combines two or more external drives and surfaces them as if they're one directory/drive to all applications. E.g. something that lets me say "create a virtual dir/drive called audio data" (that *isn't* JBOD/RAID0) and then specify two (or more) external SSDs such that the content of that dir/drive is the combined content of the solid state drives. If one has dirs Pro Logic data and Cubase data and the other has dirs Kontakt and Samples, then I'd like a single virtual dir/drive that shows:

--- data
 |--- Cubase Data
 |--- Kontakt
 |--- Pro Logic Data
 |--- Samples

When both SSD are connected, or if one of them's not connected, show

--- data
 |--- Cubase Data
 |--- Pro Logic Data

or

--- data
 |--- Kontakt
 |--- Samples

depending on which drive's still accessible. Or a flatout empty dir/drive if nothing's connected. With the explicit intent that if the SSDs that house dirs that some applications rely on aren't connected, then yes: those applications will throw errors. That's fine, and expected. I just want something that lets me surface a ton of data spread over multiple drives as a single dir/drive when they're all connected, with each SSD being "just a drive" that can also be connected to any random other computer that knows how to read/write the SSD's filesystem.

I wasn't paying attention, and now I have a RAID with a name similar to that of the boot partition. I'd like to name rename the RAID set to a name that reflects the partition name. E.g. If the file system is mounted as /Users I want to name the RAID set User_Raid Now in normal circumstances, the only time I have to worry about this is either using Disk Utility or diskutil. But both commands are moderately complex, and the consequences of a mistake severe, so having a naming convention that makes it clear what disk is associated with what RAID set and what file system helps a bunch. Here's an example: The RAID set name is SSD_System,(Red annotations) which is the same as the boot disk (Green) and which is not the same as the raid's mount point which is User_Raid (Blue) Is there a way to rename the RAID set after creation? (Yes, I can change the boot disk name. May do that yet.)

I'm given to understand that Disk Utility in macOS Big Sur does not support RAID options other than RAID 0 and RAID 1. I've got a multi-drive enclosure that I'd like to setup for RAID 5. Are there any other options for doing this? I could do RAID 1 for multiple 2-drive pairs, but would prefer to have a single, large RAID 5 volume. Any ideas?

I upgraded from *El Capitan* to *Catalina* **10.15.5** on a *MacbookPro mid-2012* , the oldest HW that Catalina will run on. Then, I created a RAID-1 drive using 2 USB disks. "*About This Mac* --> *Storage*" is **not** showing a logical 500-gb RAID-1 drive, the 500-gb disk RAID member, and the 500-gb partition RAID member is not displayed, but the 1-tb disk for this partition, and the other 500-gb partition on the same disk, **is** displayed. On the other hand: (1) "*Go -> Utility -> Disk Utility* ", (2) "*Finder*", and (3) command-line utilities all show the correct drive structure: the logical RAID-1 drive, the 2 physical disks, the 2 partitions of the 1-tb disk. Further, the amount of available drive space, on all disks, all agree. note: I did a major reorg of my data when I upgraded to Catalina. My internal disk is SSD, and Catalina automatically formatted it to APFS. Next, I emptied the 500-gb and 1-tb disks into a 2-tb disk. I decided to re-format both (hfs+). Using Catalina's RAID tool, I created the RAID-1 drive. Everything, except "*About This Mac* --> *Storage*", looks great so I am proceeding. So, I'm just reporting this and thinking this has something to do with a mid-2012 MacBook Pro being the oldest HW to support Catalina. Since data is critical to me these days, please tell me if I should be concerned about the strange "*About This Mac --> Storage*" result.

I recently bought a Mac mini to use as a NAS, among other things. I'm thinking about setting up a couple external drives as a RAID 1 (mirrored) set to help safeguard my data in case one of them goes bad. I doubt I will be using a monitor with the computer very often and I'm afraid that a dialog box or notification will sit there for months, unnoticed, while I continue to use the drive over the network. I would prefer to be emailed or notified on my iPhone. When a disk goes bad, how does the system notify you?

So, I have a 12TB drive. - This HDD is formatted in APFS (Case Sensitive). - It is a good quality Seagate HDD, less than a month old. - It is almost full with data. - I have just ordered the exact same model. - I want to set them both as Mirrored Raid 1. **Question 1:** Do I need a third drive to backup the contents of the one with the DATA, or does MacOS allow me to keep the data of one of the drives while mirroring? **Question 2:** being this a software RAID, is it possible to do the operation on one machine, to use it afterwards on another machine (both Mac Mini M4)? Or do i need to do it in the Mac where it will be finally used? (I'm still waiting for some time to receive my second Mac Mini and i'd like to speed up the process).

I have a 2009 Mac Pro that I'd like to add a hardware RAID card to. I am running VMware ESXi with various OSes running as VMs. The Apple RAID card is not what I'm looking for. I would also like to utilize the 4 hard drive bays and get 6G speeds. I have run into a few potential solutions, but have not been impressed. Anyone found a good solution?

I have 2 identical external 2T disks, mirrored using diskutility. Yesterday I realised that this volume was not mounted. I started diskutility to see what was going on and it came up as a blank screen. Tried multiple times until it eventually showed a disk info loading spinner. Eventually it showed my disks, and the raid volume, but no other useful info. Verify threw an error that I can't remember. I then started using the terminal. diskutil appleRaid list showed that one of the disks was rebuilding.... 20 hours later it is rebuilt but still won't mount. diskutil list gives the following (*trimmed to show just the disks with the issue*) /dev/disk3 (external, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *2.0 TB disk3 1: EFI ⁨EFI⁩ 209.7 MB disk3s1 2: Apple_RAID ⁨⁩ 2.0 TB disk3s2 3: Apple_Boot ⁨Boot OS X⁩ 134.2 MB disk3s3 /dev/disk4 (external, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *2.0 TB disk4 1: EFI ⁨EFI⁩ 209.7 MB disk4s1 2: Apple_RAID ⁨⁩ 2.0 TB disk4s2 3: Apple_Boot ⁨Boot OS X⁩ 134.2 MB disk4s3 /dev/disk6 (external, virtual): #: TYPE NAME SIZE IDENTIFIER 0: Apple_APFS +2.0 TB disk6 /dev/disk7 (synthesized): #: TYPE NAME SIZE IDENTIFIER 0: APFS Container Scheme - +ERROR disk7 Physical Store disk6 1: APFS Volume ⁨MediaTwo⁩ ERROR disk7s1 diskutil volumeVerify disk6 shows errors as follows: Started file system verification on disk6 Verifying storage system Performing fsck_apfs -n -x /dev/disk4 Checking the container superblock Checking the space manager Checking the space manager free queue trees Checking the object map Checking volume /dev/rdisk6s1 Checking the APFS volume superblock Checking the object map Checking the snapshot metadata tree Checking the snapshot metadata Checking the fsroot tree error: directory record (id 19): invalid hash (0x0, expected 0x14489a) of name (shutdown_time) error: directory record (id 22922): invalid hash (0x0, expected 0x3c39c7) of name (NSIRD_mediaanalysisd_3J7qIv) ... Similar lines removed error: directory record (id 31262): invalid hash (0x0, expected 0x2ae08b) of name (DB84492D-45C4-421C-8ADE-87682424AB46) error: directory record (id 31262): invalid hash (0x0, expected 0x243010) of name (E637CFBE-FE99-4CEF-B8FF-5B122D5CCA8C) error: directory record (id 378685): invalid hash (0x0, expected 0xfa1fa) of name (426AF3BB-CA79-4E4D-B3D3-59B09DCD5AD2_1_102_o.jpeg) error: directory valence check: directory (oid 0x60492): nchildren (9321) does not match drec count (9320) error: directory record (id 592626): invalid hash (0x0, expected 0x238bff) of name (Asset-tmp.plist) error: directory record (id 592626): invalid hash (0x0, expected 0x253850) of name (HistoryToken-tmp.plist) error: directory valence check: directory (oid 0x90af2): nchildren (47) does not match drec count (45) error: dstream (id 1229027) does not have an associated dstream id object Checking the extent ref tree error: (oid 0x233709) apfs_extentref: btn: invalid o_oid (0x23371f) error: (oid 0x233709) apfs_extentref: btn: invalid o_type (0x40000002, expected 0x40000003) error: (oid 0x233709) apfs_extentref: btn: invalid o_subtype (0xb, expected 0xf) Extent ref tree is invalid The volume /dev/rdisk6s1 was found to be corrupt and needs to be repaired Verifying allocated space Performing deferred repairs error: Unable to perform deferred repairs without full space verification The container /dev/disk4 could not be verified completely I've run `fsck_apfs` on the volume (disk7) and container (disk6) to no avail. How can I recover this? In theory I have 2 disks with a copy of my data, but the RAID array seems to be corrupt in some way. If I unplug one of the disks then I get exactly the same error when running diskutil `verifyVolume or fsck_apfs`

When I try iostat disk5, I get the error: iostat: could not record 'disk5' for monitoring Iostat works with my other drives, and with the individual disks which make up the RAID volume. How can I get the speed of disk5, which is an AppleRAID volume?

I'm helping a friend try to restore functionality to his MacBook and [LaCie 5big Thunderbolt 2 RAID array](https://www.lacie.com/support/raid/5big-thunderbolt-2/) . He's been editing a film and over time the RAID device has filled *completely* up. I'm not sure exactly how much total storage it offers, but it's around 10TB and there is only about 280GB of free space left. That's about 97-98% full. I remember from college that [having a spinning disk too full is BAD for performance](https://superuser.com/questions/1256074/how-much-space-to-leave-free-on-hdd-or-ssd) but this is ridiculous. His MacBook seems fine until you plug in the RAID, at which point the entire OS crawls to a halt. The Lacie shows up for perhaps a moment in the finder (and Disk Utility) but then the entire thing grinds to a halt. His MacBook crashes constantly. I think we need to free up some space on that drive or he stands to lose a lot of work and possibly some footage as well. If we can just get access to the drive and stop all the unnecessary disk traffic to it, we might have a chance. It seems clear that the GUI elements (About this Mac, Disk Utility, Finder) really bog things down. My guess is that these make numerous informational and file listing requests on a polling basis as soon as you open the window, which causes the already-distressed drive even more stress. I suspect (but this is just speculation) that there might be some kind of routine defragmenting going on or something. I was imagining that using Terminal commands to inspect the drive's information and contents might help stop a lot of the disk traffic. I was considering starting the machine in single user mode or something. Can anyone suggest a course of action where I can connect to the drive via terminal and NO OTHER PROCESSES interact with the drive? Can we stop all indexing on this drive or any byte shuffling that might be doing defragmenting and that sort of thing? EDIT: it seems clear that we need to stop Spotlight from indexing this RAID array. Unfortunately, we've tried opening the System Preferences->Spotlight->Privacy and then clicking '+' and dragging the drive into the privacy list, but the system is *so busy* that it refuses to make the change. We need to be able to prevent indexing of the drive *before* it gets plugged in somehow. **EDIT 2**: per jksoegaard's suggestion, here is the dmesg output. It was tricky to obtain this information -- the machine is quite unstable from the moment you plug the drive in. [This was the dmesg output](https://paste.ubuntu.com/p/czg7cm78cV/) just after the **Storage** icon disappeared from the finder and just before the machine crashed. **EDIT 3**: Also per jksoegaard's suggestion, we have booted the machine in recovery mode with the drive connected. The drive is much better behaved in recovery mode than it is when the Mac is booted normally. It is noteworthy that all of the drives appear in the disk utility and each has **S.M.A.R.T.=verified** and each drive appears to be in good health. We can also use the terminal to list the drive's contents and even remove files. It does look like some piece of software must be slamming this drive when the mac boots normally. Any hints on how to identify this process would be much appreciated. Also, I'm not at all certain, but it looks like whoever set it up didn't follow the Lacie installation instructions, instead choosing to set it up as Apple Raid? I don't know this for certain, but expect it might be disastrous to install the Lacie drivers & software if they were not used originally. Plz see attached images: Looks like apple raid! Each drive is listed individually. **EDIT 4:** We have been trying to work with the drive attached to the mac booted in recovery mode, and the drive is still being SUPER flaky, but you can actually work with it a bit. For example, we were able to copy a folder to another USB drive reasonably well. We then tried to delete that folder on the RAID drive using rm -r /Volumes/Storage/music/dir then we got some weird prompts like

rm /Volumes/Storage/music/dir/file.mp4a: No such file or directory
override rw-r--r-- _unknown/_unknown for /Volumes/Storage/music/dir/file.mp4a?

Answering yes to all those seems to satisfy the drive, but then when the rm completes, the flakiness comes raging back and when we try to ls -l /Volumes/Storage we get:

ls: /Volumes/Storage: No such file or directory

Continued attempts to copy or delete files from the drive eventually crash the laptop, even though its' running in recovery mode.

I have a 27" 2011 (i7 3.4ghz 24GB RAM) iMac that I just replaced the drives (1 SSD and 1HDD) in 2 years ago. It runs pretty well now, but is just starting to slow down (and pales in comparison to my 2017 MBP). I'm considering dumping about $400 into it to add an SSD (and run both in RAID0), max out the RAM an replace the thermal sensor. I'm wondering if anyone has done any similar upgrades on a machine with close specs (specifically the age)? If so, did you get the boost in performance you were hoping for or is it just asking too much from a motherboard that old?
**EDIT/UPDATE**
there are some awesome answers/comments/info here - thanks everyone... much appreciated. My main goal is to have 2 high-performing machines. Like i said, I have a 2017 MBP that is great and this iMac is still pretty good for my purposes (no gaming or 3d animation). But once this iMac starts having trouble opening big Photoshop files while I have a bunch of files open elsewhere or performing operations in Illustrator on complex drawings (which I'm just starting to see the beginnings of), it's no longer "high performing". I really like the idea of the Mac Mini, but I can't justify the $800-$1000 expense. I could sell the iMac for probably around $500-$600 (and would have no problem justifying the $200-$400 expense), but then I'd either have to buy another large monitor or live with just 2 24-inchers... which would make me sad, I think. I **am** convinced that putting the $400 into the iMac is not the best idea. So thanks for helping me get there. Decisions. Decisions. Gotta mull it over a bit more.

I just successfully merged two exact same size and model internal SSDs in my MacBook Pro mid-12 but now I am forced to run OS Catalina off of an external hard drive. I want to be able to run OS Catalina off of my RAID 0 hard drives and discount my external which I can’t have run/boot my computer longterm. Any suggestions? Is there a fix or patcher I can download?

question: when using Disk Utility to create a RAID 0 of two external HHD's, it asks to choose a **Chunk size. the options are: 16K, 32K, 64K, 128K, or 256K**. i would like to discover what another two disc external RAID 0 drive has as it came from the factory in order to know which i should choose. but i can't find out what that is. Disk Utility doesn't say, nor in its "Info" window. i even tried using the Terminal command of: **diskutil info /dev/disk3** , but that does not show the Chunk Size either. **are there any other Terminal commands or free Mac apps that would show this info?** --- backstory: fyi: using macOS 13 Ventura on a Macbook Pro M1 Max. i have an older Western Digital My Passport Pro with a Thunderbolt 2 interface (using an Apple Thunderbolt 2 to 3 adapter/dongle). it's the one with 2 HHD's in it. it came setup as RAID 0 but formatted in "Mac OS Extended (Journaled)". i want to reformat it to use "APFS" instead. so using Disk Utility, i deleted the RAID and reformatted the drives. then upon using Disk Utility's RAID Assistant, i selected the RAID type to RAID 0 and selected the two newly reformatted drives. then on the next screen (Set Properties), under where you choose the Name & Format, there's a setting to select a "Chunk Size". i've never seen this option before (granted it's been many many many years since i needed to re-RAID something), and i can't figure out which option to select... the Chunk size options are: 16K, 32K, 64K, 128K, or 256K. everything i've found to read on the subject says that's determined by how big the files you're working with are. to choose a small K when working with large videos & graphics files; and to choose a large K when working with smaller text based files. but what if you have a mix for ALL kinds of files & sizes? what would be the optimal Chunk size for a general purpose drive? yes, i could just choose the middle one (64K) but i don't know if that's optimally average or if leaning to the left or right of middle would be better for such a mix of file types & sizes. i did contact WD support and instead of just telling me what Chunk Size the drives came from the factory set at, their 'only' solution is for me to download/install their disk utility app. i had problems with that app working well two computers ago, so chose to not install it on my previous & current systems. i would rather a solution to be knowledge rather than 'another' app to clutter my mac innards just for this purpose. thanks.

I have two SSDs in an external enclosure, exposed to the OS as independent drives. I want them to appear as a single encrypted APFS volume, with RAID 1 mirroring. I'd like to set up RAID via the native Disk Utility, rather than third-party software like SoftRAID. In Disk Utility, I can create a RAID 1 set containing the two drives. However, in the format choices I only see APFS, not APFS (Encrypted). If I create the RAID Set using APFS, right-click the volume in Finder and choose "Encrypt", the operation succeeds, and the volume works. However, Disk Utility immediately shows the RAID Set as "Offline" with one disk "Missing/Damaged". The same thing happens if I use Disk Utility to Erase the volume as APFS (Encrypted). Is there any way to encrypt the volume without breaking the RAID Set?

I did a lot of research already and it seems like this was definitely possible before AFPS (see http://hints.macworld.com/article.php?story=20041013121106176) . The command diskutil appleRAID enable mirror /dev/diskXsX could be used to group an existing drive into a RAID1, and then you could add the new drive and 'rebuild' the second drive. However, I'm trying this with an AFPS Time Machine drive, and I'm getting Error: -69819: File system resize support required, such as HFS+ with Journaling enabled. Any advice? I don't have another 6TB drive to temporarily offload the Time Machine data to, so I need to figure this out if it's possible.

I’m using M1X MacBook Pro 16 inch (2021) running macOS Monterey 12.3.1 with 4-bay hardware RAID enclosure from QNAP (TR-004) holding four 10TB Toshiba HDDs. The enclosure spins down the HDDs soon after they become inactive and I’d like to have them spinning all the time (granular control is desired, though; e.g. spin during the day, spin down at night). Although I unchecked “Put hard drives to sleep when it’s possible” (wording may slightly be different) for both Battery and Power Adapter menu on the system preferences, the enclosure still spins them down. Until a few weeks ago, having those options unchecked had been working. I believe software (most likely macOS) is to be blamed for this malfunction. Does anybody know how to keep them spinning or how spinning/spin-down work on macOS? Is this controlled by S.M.A.R.T. or something else? If any of you happen to know an app that has granular control over HDDs’ behavior? Thank you in advance!

I have a Mobius 5C external 16TB USB-C RAID connected to a Mac Studio Ultra. Whenever I try to copy anything to it I get an instant crash and then restart. The RAID is formatted as HFS+ and I think that might be the problem but I'm not sure. I tried to convert the RAID to APFS in Disk Utility but failed. I'm trying to avoid an erase and APFS partition. (Monterey 12.6.1)

I have always used Software RAIDs, either Apple-provided, or via SoftRAID, etc. I am about to re-zhuzh my arrays and decided to do a little research beforehand… and On Apple's site, there is a statement, clear as day… # RAID 1 (mirroring) for disk redundancy # >Mirroring improves reliability by writing the same data to two or more disks. If one hard drive mechanism should fail, the second disk still contains all the data. At least two hard drives are required for mirroring. **Mirroring does not provide performance improvements.** If the hard disks are not the same capacity, the smaller size will be the amount of disk space used on both drives. Disk Utility determines this automatically. I was always under the impression that, as there are TWO platters for READ operations, that READ performance with a 2-Drive RAID1 mirror would be _somewhat improved_. This contrasts with write speed, which remains the SAME, as the drives have to both write the same data at commit-time, so as to sustain a mirrored copy of the data. However, when reading I had thought that the array acted similarly to a RAID0, *striping the reads accross both drives*. How is RAID1 is *supposed* to work? If so, is Apple.. 1. just saying there is no improvemnet to cover their asses, or 2. are they actually not implementing RAID 1 to its full extenent? (Does SoftRaid 4.3 claim to do this?) According to Wikipedia… > In RAID 1 (mirroring without parity or striping), data is written identically to two drives, thereby producing a "mirrored set"; … The array continues to operate as long as at least one drive is functioning. **With appropriate operating system support, there can be increased read performance, and only a minimal write performance reduction**;… So it is Possible, but Apple says there's does not see any speed benefit… But in practice, is there any measurable increase in speed for reads with Software Raid 1 (via Disk Utility)?

I have a LaCie 60TB RAID array. I've had it for a couple of years, but I am wondering how often I should do a "Consistency Check" on it. I don't know a whole lot about RAIDs. It's formatted HFS+, so I think this is a different than defragmenting. LaCie don't mention doing this as a routine in the section of the manual regarding the subject.