RAID!!!

[UPDATE Sunday March 31: Readers in the comments talked me out of my brief infatuation with RAID. I'll leave this post alone, but my backup plans no longer include RAID. Please see the next post for my backup plans as they developed from the collective advice I got from readers. Thanks! —Ed.]

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Because I am an unwilling slave to authoritarian Big Brother corporations and my mind has been taken over, I can't help thinking of the old Raid bug spray commercials that featured insects happily destroying human property until the can of Raid comes out, at which point they all shriek "RAID!!!" and flee.

But what we're talking about here is not that, but computer storage. In the computing world, RAID stands for "Redundant Array of Inferior Disks." It's an umbrella name for several strategies for ganging physically separate hard drives together in various ways to make them work less poorly.

There are several types. The first is RAID 0 (zero), so called because it offers zero protection from failure. Photographers don't need to mess with this type; all RAID 0 indicates for us is that we must momentarily become sad and feel sorry for videographers.

Then there's RAID 1, which is the important one for us. In RAID 1, two identical drives are linked together in the same volume, which are often placed in the same enclosure. The capacity of the array is the same as the capacity of a single hard drive, so you are getting one for the price of two plus the price of the enclosure (such a deal!). But the salient point is that any file you copy to the first disk is automatically copied exactly on the second one. So, if when one drive fails, you can keep on working. If you remove the bad drive and insert a fresh one that's still good, RAID 1 will immediately begin rebuilding the new drive from the surviving old one.

There are many other types of RAID, including RAID 5, RAID 10, RAID Track 9 1/2, RAID 42, and RAID TTPoP (to the power of Pi). All of these types and many others not listed may be ignored with a devil-may-care attitude and a dismissive wave of the hand on account of us not being smart enough to be IT persons.

You might think that RAID 1 means you are also automatically backed up, but oh no, bug-spray-breath. Because good backup hygiene demands that you still be backed up even during a failure. When one of the drives fails in a RAID 1 setup, you would then temporarily have all your data on one physical drive, and that is not enuff. (Isn't it annoying when people try to be cutesy by spelling "enough" like that?) So a RAID 1 box is highly reliable, much more so than a single external drive, but you still need to back it up somewhere else. How you do this is the same problem you had in the first place, but never mind.

Note that stated RAID 1 capacities must be cut in half. For instance, a 4TB RAID 1 box has two 2TB drives inside and offers 2TB of storage. I hope I don't need to say out loud that if hard drives actually were reliable, we wouldn't need RAID setups in the first place.

You might already have one
What some people don't realize is that you can set up a RAID 1 in MacOS Mojave using regular old external hard drives. I do not know if this is better than or worse than or the same as the bespoke solutions.

Start with two identical hard drives. If not new, make sure there's nothing on 'em you want to save. If new, make sure they are formatted for Mac—"Mac OS Extended (Journaled)." Do a Spotlight Search to find Disk Utility if you don't already know how to find it. Under the File pulldown menu in Disk Utility, there's an option called "RAID Assistant." You can use RAID Assistant to set up Striped (RAID 0), Mirrored (RAID 1), or something very charmingly called "Concatenated (JBOD)." This last is pronounced "jay-bod," and, this is true, it stands for "just a bunch of disks." I'd use JBOD just for the name alone if I could think of any reason to do so. A JBOD is a volume that just lumps one disk with another resulting in a larger drive.

The best Thunderbolt 3 dock

So while I wanted a super-duper hardware RAID 1 in its own fancy enclosure, they're all expensive, and I ended up just buying two 4TB Western Digital My Passport portable drives which I plan to set up as a RAID 1 in Mojave. Offsite backup courtesy of BackBlaze. Good enuff (?).

If you really want to go the Ferrari route, try a RAID5 setup with the awesome made-in-the-USA CalDigit T4. Way above my pay grade, so you're on your own with that. CalDigit, by the way, is the company that makes the best Thunderbolt 3 dock for photographers, the famous TS3 Plus, the one that has a UHS-II card slot in it and that can charge your laptop at full speed and run your monitors and has umpteen ports and on and on. There are glowing reviews all over the Web.

Enuff! (Er....) And now, many readers will write comments that I am not smart enough to comprehend, but which I am hopeful of learning something from anyway.

Mike

P.S. It's actually Redundant Array of Independent Disks. Originally inexpensive, says Wikipedia.

But you knew that.

Original contents copyright 2019 by Michael C. Johnston and/or the bylined author. All Rights Reserved. Links in this post may be to our affiliates; sales through affiliate links may benefit this site.

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(To see all the comments, click on the "Comments" link below.)
Featured Comments from:

Speed: "Many years ago I worked in a bank. Every Friday afternoon a professor from the music department at the local University brought in some sort of computer storage media, put it into his safety deposit box, removed last week's media, said 'have a nice weekend' and left. He was a man of few words. And fewer worries about backups."

Jim Richardson: "I must say that after a while MEGO when it comes to RAID. And since what I really wanted was data security, not data availability (as 01af so nicely pointed out) I have run my business on JBOD. To me the giveaway is that RAID users always have stories to tell. I don't want stories to tell. I want to know where the files are."

["MEGO" means "my eyes glaze over." —Yr. Hmbl. Ed., working so you don't have to.]

Bob Johnston [no (immediate) relation to the ed. —Ed.]: "Beware the RAID 1! I am retired now but used to work for a computer company. If I had a pound for every unrecoverable failure of a RAID 1 array I would be a rich man. I won't bore you with the details but there are several failure modes that can render a RAID 1 unrecoverable. The simple kind of RAID is intended to keep you working seamlessly, so for Mike there is a value. If his disk fails while he is writing his blog he won't be interrupted. But it does not negate the need for a backup. Therefore, in my opinion, unless you can afford RAID 6, RAIDs are of little value to anyone who can wait a while whilst their data is rebuilt."

Bill Tyler: "Several years ago, I was working at a very large software company on very large storage systems. We had thousands of servers, each with lots of disks attached to RAID controllers. At that time, a petabyte was a lot of storage, and we had lots of petabytes. Anyhow, the official line was that we had nice redundancy because each RAID array could withstand the loss of a disk. Fortunately, each byte of data was also stored on a different RAID array on a different server. I say fortunately, because the bit that wasn't considered in the official line was the RAID controller—the thing that all the disks attached to—as a point of failure. If that goes, the whole RAID array is toast. The point was driven home forcefully when we discovered that a batch of those RAID controllers were subtly defective.

"Whatever you're using to create and maintain a RAID array, whether hardware or software, is a single point of failure. Be warned, and use RAID judiciously."

Rodolfo Canet: "RAID 1 doesn't protect you from accidental deletions. Use one of your two new drives for data and tell Carbon Copy Cloner [MacOS only, 30-day trial available —Ed.] to back it up to the second one at regular intervals. Easy and cheap, and you can work directly from the second in the case the first dies and you don't have the time to buy a new one (that's the problem of relying totally on Time Machine)."

Edward Taylor: "If you want to be wealthy, design a permanent storage solution. There is no practical permanent solution at this time. Back up once, store in a drawer forever, no worries about it becoming unreadable in the future. I am shocked that this has not been accomplished yet after at least 40 years of widespread computer use. It is really absurd."

Comments

[Kenneth Tanaka]

RAID is actually "Redundant Array of Inexpensive Disks", Mike. :-0

[Rob de Loe]

Let me join the large group of people who surely are going to tell you that RAID is not a substitute for backing up! Maybe you knew that already. Many people don't.

I use a RAID array as one of several backup devices. I have many backup devices...

[Stan B.]

I'm guessing putting the ALL TIME GREATEST HITS on these wouldn't hurt...
http://www.mam-a-store.com/golddvd.html

[Paul Richardson]

Thanks so much for posting this. I look at the options and become so overwhelmed that I never act on them, but I need to - and quickly - as I’m about to hand over my MacBook Pro due to the ridiculous sticking key issue, and who knows what might happen. I currently do use Backblaze, but I recognize that that isn’t enough.
Thanks again for the clarity.

[Jim H]

I have probably had a dozen hard drives fail over the years, so I have started using 1TB SSDs - solid state drives - for my MAC Time Machine backups. Time Machine can manage two backup drives, alternating every hour, bwtter tthan a RAID in one case IMHO. I also have my backup drives on a UPS in case of power failure. Then, every month I do a separate bootable backup and swap it with last month’s in my bank safety deposit box. Amazing what you learn from CA wildfires!

[Does Time Machine also back up external disks? That's the problem with my Time Capsule backup--it doesn't handle external drives. Since my computer has a 512GB SSD, and I have about 1.6TB of photos and music, I kind of need a solution for the external drives. Plus, I've just splurged on the new computer and paid Uncle Sam his pound(s) of flesh, so I really can't spend a lot of dough. --Mike]

[Mike]

I would not do RAID5 these days with spinning rust hard drives, only SSDs. The issue is that drives are so large, there is a not insubstantial risk of another unrecoverable error while rebuilding a RAID5 array at which point you're completely SOL (think how long it would take to say, read 3-4 8tb drives to rebuild the data on the failed drive). SSDs are ok because of their greater reliability and because they generally fail by going into read-only mode. RAID6 is probably the bare minimum I'd recommend, but really RAID10. Even RAID1 is preferable.

Sadly MacOS has terrible tools for doing RAID. I've actually resorted to building a storage appliance using FreeNAS and server grade hardware, serving up storage via AFP, SMB and iSCSI. I keep it in the closet because of the noise.

[Matt Mills]

A good option if you don't want to think about it too much, and can throw a couple hundred extra bucks at the problem, is a NAS (network attached storage) like the Synology https://www.amazon.com/Synology-bay-DiskStation-DS418-Diskless/dp/B075N17DM6 (which I have and use). Buy the thing, buy four bare drives, plug it all together, and you're done. It shows up as a network drive, and is optimized for getting the most storage out of whatever drives you put in it, while maintaining data integrity.

As someone who has administered my own RAID arrays before, I can't recommend an appliance that does it for you enough.

[Moose]

"In RAID 1, two identical drives are linked together in the same volume, which are often placed in the same enclosure."

Therein lies the rub; whatever external thing happens to one disk happens to them all.

Randomly Accessed Moose Disks is a system which also uses two identical disks. One lives in the computer, the other lives in a fire resistant little safe - at the other end of the house.

No, not automatically up-to-the-instant. Yup, requires me to manually plug the backups into the "toaster" and run the backup.

Yes, I could lose some work, although not originals, as I make sure to back-up before formatting any full flash card.

Also, the B-U disk has never run for more than a v. few hours, by the time it is replaced with a larger one. In RAID arrays, the disks wear/age identically.

I do this for four different disks, including an SSD clone of the SSD boot drive. So far, AFAIR, the photography pairs have been 750GB, 1.5 TB, 3 TB and now 6 TB. With each upgrade in capacity, the old set has moved down the totem pole to the next category of stuff, with the hardly used B-U becoming primary.

[David Dyer-Bennet]

I'm rare in using mirroring (and, using FreeNAS, I can run bigger mirrors than just two-way; with the huge drives today, single redundancy is widely believed not to be sufficient).

Most people use the "parity" models, RAID 5 and friends, where an array of disks has 1 (or, among the friends, 2 or 3) disks added to store redundant information. So, in an 8 drive case, you might have 6 data drives and 2 parity drives, given a usable space of 6 times the size of the drives (all the same size for this), and able to withstand loss of two drives without losing any data. With 6TB drives (which are cheap at the moment) that means 36 TB of usable space (which is vastly more than most people, even photographers, need).

You do also have to know how to notice that a drive is reported failed, and how to correctly identify which drive, and how to replace it (on the fly).

[jseliger]

There are Drobos, too. https://www.drobostore.com

[SteveW]

I'm kind of likeminded in my approach, and I also have a Mac Mini (2018) running Mojave. I have two 1TB external Seagate HD's configured as Time Machine back ups. Not mirrored, but Time Machine uses both and alternates. I also have have two more 1TB drives for extra storage, those are mirrored (Raid 1). Plenty of space. And to go over the top, I use the 256GB SSD in my old Mac Mini (late 2014) as an external drive as well by booting it in target disk mode. Why waste the resource? And it's super fast, connected by lightening cables. More space than I need honestly, but it's so inexpensive, and long story short mirrored drives are the only way to fly.

https://www.amazon.com/Seagate-Portable-External-Photography-STDR1000100/dp/B00H4XH5FY/ref=sr_1_3?keywords=seagate+1tb&qid=1553895339&s=gateway&sr=8-3

[Kurt Shoens]

Having a local backup (MacOS makes that easy) plus offsite backup sounds very thorough to me.

RAID is great when you need to keep working even though a drive failed. On the other hand, RAID doesn't protect you from yourself (e.g., accidentally deleting something) or viruses or whatnot.

I personally don't bother with RAID because I can afford to have my computer inoperable while I replace the broken drive and restore from backup. I will also note that RAID systems are very difficult to implement well, especially on ordinary computers. Even in the simplest RAID-1 organization, how does your computer know it has written both copies across all the scenarios like computer crashes and power failures? With RAID, it's possible that you have silent data corruption lurking that you won't see until a drive fails. Also know that drives fail in many vexing ways to add to the complexity.

Short version: backups are good and offsite backups are even better.

[John E]

Everybody has a disk failure story, here’s mine. RAID1 setup, I had it, yes that’s the way to go. But, a good backup plan is even better. Lightning hit a power pole down the block and some bad stuff got into the coax cable coming into my modem and into my computer. The computer still functioned albeit one of the RAID1 drives no longer responded and the internet port was toast. No problem, the mirrored RAID1 drive kept things going while I ordered a new computer. The plan was to transfer all critical files via USB to the new computer when it arrived in a few days. But alas, the remaining RAID1 drive (or supporting hardware) decided to crater before the new computer arrived. I was fortunate in that I performed backups to external drives although my last backup was 3 weeks old, so I lost three weeks of data. Not bad considering everything. Moral to the story is it’s ok to have SOME faith in the RAID1 redundancy but don’t let that lull you into believing it is a substitute for a real backup plan.

[Jim Freeman]

We love it when you talk techie.

[John Camp]

I save all my work to two separate flash drives, and move all the saved files to a desktop file that is automatically saved to the Microsoft cloud. That should take care of it. I don't know how much or how long the cost of a RAID array would pay for cloud storage, but it would be a lot of storage for a long time.

[Jeff]

They may be inferior but they are also independent: https://en.wikipedia.org/wiki/RAID

[Michael Perini]

Do you really need RAID?
If you have Time Machine backing up all day long, and off site cloud backup you would seem to be covered fairly well.
With Apple’s notoriously stingy and expensive boot drives I have begun using the internal SSD as a boot drive with the OS and applications folder, and keeping Data (everything else or basically your home folder) on a separate 2TB SSD on the Thunderbolt 3 buss
Ever since I separated data from OS my machines have had far fewer issues, and when I have them it is an easy fix .
Time machine backs them both up all day long, plus cloud backup.
I also keep daily backups of my photo library with approximately monthly doomsday backups at my other house.
But that stuff is sort of belt & suspenders
Ps you can also clone your boot drive to a tiny ssd and be up and running in 30 seconds.

[Oskar Ojala]

Software RAID is not a bad alternative to dedicated hardware, but using two external disks is an..interesting choice. Though maybe I'm just being old fashioned, nowadays it could work.

An anecdote here is that I used to have a NAS that I used mainly for backups and distributing files among my computers and with a conservative RAID 5 setup it was supposed to be foolproof, but the network adapter broke! Turns out it takes effort to figure out what the actual configuration of the device is and how to read the data with the drives in a computer. Luckily I had everything backed up offline.

Also, do offline backups! E.g. a fault in the power distribution could fry your online disks and RAID won't help with that.

[PDLanum]

I use RAID 1 but it is in my desktop. I have two arrays a 1TB and a 6TB array all internal. I have a cheap NAS that I use for system images and "backup" for odds and ends plus my RAW images. Laptops just do not cut it, I have a few laptops but I don't do "real work" on them. I have used my old laptop as a device in the field to do quick edits.

In my opinion, just having a laptop is very limiting because you really can't get enough disk in it to do enough work across jobs. I have 500GB SSD's to get copies of my RAW data off of my SD cards, but being dependent on either a laptop or a All in one. I like expandability on my terms.

I build my own devices so no single manufacturer has a device that really fits my needs. Some can come close, but I just don't like them.

Now as for RAID, RAID is not and has never been a substitute for backups. When you hit the delete button on a RAID device, the data are deleted from the array, nothing to recover, no recycle/trash bin. Backups are always physically separated from the source data. RAID is essentially to ensure hardware fault tolerance, that is about all there is to it.

As for background, I spent 30 years working in the IT support field. My last paying job was overseeing a system providing Disaster Recovery service to over 100,000 desktop/laptop clients. The system had just under 5PetaBytes of storage. I fully understand RAID, backups, uptime, fault tolerance and high availability.

[c.d.embrey]

Gear is boring, be it camera or computer—'nuff said 8-) RU OK with that?

Seriously, why hard disks? SSD (Solid State Drive) now sell at Amazon for $120 to $150 per terabyte https://www.amazon.com/s?k=1+TBssd&ref=nb_sb_noss_2

[Robert Harshman]

It's simply a matter of how much you are willing to pay vs lose. What is the value you place on your archives?

Having at least two identical drives with the same images is the cheapest and relatively reliable way if you discount home fires or flooding or other natural disasters. It's easy to sync drives with many freeware software. And if you store them at your office and home even better.

My office and home are the same thing, so I have a gun safe that I keep older backups in. And move newer drives into after significant amount of new work after the original camera media is reformatted for new images. At any one time I usually have at least three original RAW sets of images. Since I mainly do computational photography I only really need to safeguard the RAW files. I can always recreate the final output as painful as that might be.

I decided to not use the cloud as it was simply too expensive as I have about 100 terabytes of image data currently. I work in a world were small files are over 22K in pixels. Large files are well over a 100K in pixels. It why I still spend over 6K in new computers every few years.

[Mark Kinsman]

I always preferred RAID 10 for data storage during my days in IT for the redundant mirroring using 4 hard drives in pairs of two. Currently I use a 16TB Glyph Studio RAID Thunderbolt 2 configured to 8TB . That and Backblaze give one some piece of mind.

[Cal]

So I basically came to a similar solution and went with a "JBOD" (just a bunch of discs) enclosure, with its own power supply and controller card. It makes it easy to put all those extra hard drives to good use for storage and backup.

[01af]

The purpose of RAID systems is to improve data availability, not data security. So unless you're running a server, RAID is not for you. In order to avoid data loss, just have two (or better, three) independent hard disks, and keep one of them outside the house (e. g. in a friend's house or a safe deposit box).

[John Shriver]

What's built into Mac OS X for RAID is software RAID. All the work is done inside the operating system.

External RAID controllers provide hardware RAID. They can be faster than software RAID, especially for versions like RAID 5 requiring heavy computation. They can also have fancy features like being provisioned with spare drives that will be automatically provisioned when one fails, rebuilding that drive from the parity data.

The downside of external RAID controllers is that they have software in them. Software that in quite a few cases proves to the less reliable than the software RAID. Such bugs can cause disastrous data loss. I've seen "stop ship" orders issued by vendors when bugs were found in external RAID controller software.

Also the "on disk format" of the external RAID controller data can be proprietary, making data recovery harder if the RAID controller fails. To be really reliable, you really want to have a spare of the external RAID controller, so that you can recover the data if the controller fails.

One thing that's important to note is that RAID is generally a foolish idea for solid-state disk drives. They don't fail randomly like spinning (magnetic) hard drives, they wear out after a certain number of write/erase cycles. Having both the drives in your RAID 1 mirror pair fail at exactly the same time is a terrible failure mode.

[MikeR]

Do you remember the "Sweet Sixteen" speaker system? An array of 16 cheapo small speakers wired series-parallel.

(Maybe you're too young?)

[Michael Perini]

Mike Time machine will back up any drive you tell it to, and exclude any drive you tell it to.
If you were to buy a 2 TB external SSD attached over Thunderbolt 3 and separate Boot Functions from Data functions, Time machine will back them both up to any drive you want. Depending on size your time capsule should do the same thing.
I do believe you can add an external disk to a time capsule but am not certain.

https://www.macworld.com/article/3153995/how-to-make-sure-time-machine-backs-up-external-drives.html

The advantage of doing it this way, is that your OS, Applications & Data will all benefit from SSD/ Thunderbolt 3 speed instead of a single spinning drive over USB 3 (that includes RAID1)

RAID arrays certainly have their place, but I don't see the need for it in a simple setup like yours

[Tom R. Halfhill]

Be aware that flash memories (SSDs and USB sticks) aren't ideal for archival storage. Over time, the bitcells gradually lose their data unless it's rewritten periodically. The minimum industry standards for data persistence are only three months for "professional" SSDs and six months for "consumer" SSDs. Of course, the drives will almost always retain data for longer periods, but those are the minimum standards that the vendors must meet. Newer and larger-capacity drives may have less persistence than older and lower-capacity drives because their smaller transistors hold fewer electrons -- and the electrons are your data. Recently I had a USB stick fail to be readable after only a few years in a desk drawer. But I have much older USB sticks that are still retaining their data, probably because they have larger transistors.

[c.d.embrey]

I'm writing short stories, so I don't need much space on my Time Machine. I have a $40 SanDisk Cruzer 256GB USB 2.0 Flash Drive plugged into one of four USB ports of my 21.5 4K iMac. The 1TB hard drive has 978GB still available after 2.5 years of use https://www.amazon.com/SanDisk-Cruzer-256GB-Flash-SDCZ36-256G-B35/dp/B01EHG3GVM/ I also have a 128GB SanDisk thumb drive for photos/videos, plugger into another USB port.

Everything is also backed up to iCloud.

For writing I use iA Writer on both my iMac, and my iPhone XS. iCloud keeps iMac and iPhone in sync.

[Peter Croft]

Back in the early oughties I paired a couple of drives in RAID 0, aka striped, to get the speed needed for HD video editing. I also put my still images on there too when my scanned TIFF files were 30MB and took about 15 seconds to open.

But in 2013 I moved house and physically separated the striped pair for reassembly in a new case. Something got confused and despite months of trying, I never recovered my material. I grieve still, as every so often I recall an image in my mind, only to remember that it's gone forever. I did have CD-ROM and CD-RW (remember those?) backups of most of them, but many images were lost.

I do compressed backups to another drive now, but not regularly enough, I admit. It won't happen again...

My worst disaster was in 2014 as I was preparing a school reunion magazine using DTP. It grew to nearly 450 pages and was stored on my C drive, an SSD. I did have a backup on another drive, but it was about a week behind due to the pressure as the event approached. Of course, the SSD chose that time to fail. I did have my backup, but I lost nearly a week's work on the magazine with about 10 days to go to the event. It took a couple of days just to rebuild the system before I could get going again. That was stress.

I still use an SSD as my C drive but I made an image of it to a 256GB microSD card a few days ago, prior to replacing the SSD with a 512GB one. The 256GB microSD was only about $110 and can be reused for video in a camera.

I do intend to buy a NAS soon as being able to access everything over the internet while travelling would be good. Otoh, I could just have a holiday.

[Bear.]

Hi Mike,

Time Machine DOES back up external drives, or specific folders on external drives from them (e.g. a "Photos" folder). For some reason, the process set up by Apple is backwards (pardon the pun). By default, Time Machine excludes external drives from backing up to the selected back up drive. But you can change the default to cause external drives or specific folders on them to be included in a Time Machine back up by excluding the external drives or folders from the default exclusion, thereby including them. I did say I said it was backwards.) Here's how.

A. Before you begin: make sure your Time Machine back up drive has (A LOT) MORE storage than the external drives or folders on them which you wish to back up.

B. Steps to back-up a whole external drive.

(1) Open Time Machine in System Preferences and choose options (bottom right). You will get a list of external drives that are EXCLUDED from the back-up.

(2) Select any external drive that you want Time Machine to back up and click the MINUS button (bottom left) to remove it. (Be careful not to select the back-up drive to back up to itself, if it is in the list.)

(3) That's it. Time machine will now INCLUDE that drive when it backs up to your selected back-up drive.

C. Steps to back up specific folders stored on an external drive.

(1) Remove the whole external drive storing the folders you want to up from the excluded external drives list by the above process.

(2) Click the PLUS button (bottom right). It will open a "finder" window.

(3) Select the drive you just removed. That will give you a list the folders on the drive to be EXCLUDED from the back up.

(4) Select all the folder/s you do NOT want to back up. Click the PLUS button (bottom left).

(6) That's it. Any folder/s you did NOT select in the previous step will not be INCLUDED in the back up to your selected back-up drive (i.e. because they do not appear int he excluded options list).

As a final note, you don't need to use a time capsule. Most external drives are Time Machine compatible (if formatted for HFS + or APSF). I use an (ancient in computer years) Drobo N plugged in by ethernet into a local network wi fi router, and it works perfectly to back up both my iMac and numerous external drives over a local Wi Fi network - even if it is very slow.

[Aravind]

Raid 1 is the bare minimum. However, I would recommend not using two "identical" disks in all sense. Yes, they have to be identical in size. But preferably, you should be using two disks of identical sizes from two different manufacturers. If from the same manufacturer, at least ensure that they are from two different manufacturing batches.

I have had two disks in a RAID 1 configuration (bought from the same vendor, from the same manufacturing batch) fail within a couple of weeks of each other. Fortunately, had backed up the contents of the second to a hard disk from another manufacturer before it failed since I had a hunch that the first one's failure mode might repeat with the second one.

[Mike Farley]

Backing up your data is a good idea but with your approach it remains onsite. A fire, burglary or some other untoward event could still result in losing everything. As I recall, you have an outhouse and as an absolute minimum I would keep an external drive there, updating it regularly. Geographical separation of 5 - 10 miles is better if you can arrange that. Should anything happens which simultaneously destroys both copies, recovering your data is likely to be the least of your worries. Backing up to the Cloud is another option, particularly for anything you especially do not want to lose.

[Wolfgang Lonien]

rsync is your friend. Works even on Macs, and there are plenty of resources trying to explain it. Here are some I found with a quick search:

https://www.techradar.com/how-to/computing/apple/using-rsync-to-keep-your-files-in-sync-1305698

https://www.haykranen.nl/2008/05/05/rsync/

https://static.afp548.com/mactips/rsync.html

We're using it since years to remotely back up the whole household (Linux) to RAID drives. Totally painless and idiot-proof, just what I need.

[Steve Jacob]

Forget RAID. It was invented when disks were expensive, slow and unreliable. In my experience, a lot of RAID implementations cause more problems than they solve - especially when you can't find like-for-like drives to swap with failed ones.

Typical low-cost RAID implementations are more likely to fail than an SSD (IMO). The only reliable ones are built into the controllers on dedicated storage racks. These are industrial grade devices - just like the ones used in cloud-storage server farms.

Most of us home users can survive with a few minutes loss of data every 5 years or so. SSDs are blazingly fast and reliable, and quite cheap when all things are considered.

In terms of backup, RAID has the same issues as any disk. All local issues that cause failures will affect all the data. Viruses, DOS attacks, brown-outs, floods, fires, break-ins etc.

Near-time cloud backup means you seldom lose more than a few minutes of work, and the backup is protected from any environmental issues. I can also access it on the road, which is handy, and from all my Android devices as well as my laptop.

My advice is to buy enough cloud storage from Apple and use Time Machine to sync your important folders (documents, etc.) in real time.

I get free cloud storage with my MS Office account and Adobe subscription. So far, I have not required any more.

For large volumes of images I only sync the files I plan to keep. I sort all the files in Bridge when they are uploaded from the camera, and copy the ones I want to edit to a synced folder and import them to the LR catalogue.

If I lose the rest, it's not a big deal. It also means my catalogue is smaller, and I use a lot less cloud storage. Because raw files are not updated, only the XMP files, JPEGs, TIFFs and PSD files are synced, which doesn't take long.

However, I still make a periodic backup to an HDD which lives at a friend's house... just in case.

[Andrew Lamb]

Or shoot film.

Sorry. Couldn't resist.

[Thomas Mc Cann]

I'm sometimes bemused with all this talk about secure storage of ones precious photos. How precious are they? Do people really have 4tb of precious photos ? And never mind the hard drive dying what happens to all this precious storage when you die. We can't all be Maiers either in substance or luck

[Trevor Johnson]

Carbon Copy Cloner, (Mac only), is my recommendation over Time Machine.

I am unsure exactly what you are trying to achieve by using two external drives in a RAID 1 setup. If you want a simple RAID solution, something like the WD My Book Duo works well.

[Rob Campbell]

If ever there was an argument for film days...

Rob

[Paul Farr]

I know its advert (although its very old so may no longer be relevant) so you might not want to publish this link, but I always found the "Tao of Backups" a funny and well explained synopsis of what, why and how we back up

http://taobackup.com/

[Michael T.]

Please don’t confuse TimeMachine with backup. It is not the same. And unless you are an expert I would not consider configuring my own RAID system. And as others have pointed out Apples RAID implementation is in software. An NAS system (drobo, synology, etc.) is the way to start. Also careful thought into what gets backed-up: e.g., a bootable version of your entire internal system, separate back-ups for documents and photographs. Also be very careful with the type of hard disks you purchase: paying a little more for data center quality vs. consumer grade. And, of course, good SSDs will be more reliable than moving magnetic media. Lastly design your system knowing that disks WILL fail.

[Dave Van de Mark]

As an old time computer builder and repair guy, I can't tell you how many folks I knew who lost stuff in the early days of RAID when hard drives were REALLY bad! As a result, I have always been leery of it. An exception could be a complex RAID scratch disk array.

To me, the key thing now is hard drive storage is relatively cheap, so my MacBook Pro laptop is connected to 2 external Thunderbolt-2 cases, each of which have (2) 5yr warranted (best quality) spinning hard drives of 2-3 TB capacity. I make sure to always leave plenty of empty space - at least 20%. These are my main file storage drives and they double as scratch disks. THEN, I back them up to about 8 WD passport drives of various sizes and ages, keeping a good number of them "off-campus". Fire, accidents and theft can be as bad as hard disk failure!

[Peter Wright]

There does seem to be a disproportionate representation of IT types in the photography community (and nothing wrong with that). But this means that when discussion of computers comes up, the recommendations tend to get overly complex overly fast.

I don't believe you need any sort of RAID. Time Machine can keep track of any drives you assign; internal or external. Right there that saves you from a lot of problems. However, as you have a 512G SSD, I imagine you will be keeping all your pictures on an external drive (faster is better for this one). Then all you need is backup software (I find ChronoSync works very well, is inexpensive, and all upgrades are free) for a second external drive. That protects against drive failure, and data loss. If you want cataclysm protection, then adding another drive off-site (could be at a relative's house) that swaps with the first backup on occasion, will cover that as well.

That is much simpler, less costly, and easier to manage than any of the RAID configurations you mention. RAID 1 is really for avoiding system down time in the event of a failure (important if you customers will go elsewhere while your servers are not accessible), and RAID 0 is for fast access. I think that given your new Mini is fast and has TB3 ports, there is a case for making your main external drive a RAID 0 just to speed up normal workflow, but only if you spend lots of time processing large picture files.

The simpler it is to manage, the safer your data will be.

[XCosteas]

A couple of practical, OS X-specific, points: with current Macs, it's obvious one must go the Thunderbolt route. With older systems, however, the only affordable direct-attached-storage (DAS) solution is to use eSATA, and OS X supports ASM1061-based chipsets (found in sub-$100 PCIe cards) out-of-the box. Firewire, as we all know, is dead, and USB just doesn't cut it.
A second- (or third-) tier backup to a NAS is also necessary, for archival purposes, but is a different story altogether. DAS (and not NAS) allows working with one's photos in, say, Lightroom, and that's what we are talking about in this post by MIke.
My sense is that it's easy to manage multi-disk, directly-attached (clarify: not NAS) enclosures, but not with Disk Utility, as it's too rudimentary.
Two products, one proprietary and non-free, and one open-source have been available for years: SoftRAID (google SoftRAID LLC), and OpenZFS. I use both extensively.
My tribulations with all things storage, as pertaining to amateur photography, can be found at: https://lycabettus.wordpress.com (eSATA RAID mostly).
The nice thing about this approach is that it's affordable, scalable (can use HDs, SSDs, 2- to 8-disk enclosures) and future-proof (running nicely since 2009 and will probably work once I can afford Thunderbolt).
Hope this helps.
With greetings from Athens,
Xen

[Bruce Rubenstein]

https://en.wikipedia.org/wiki/RAID

RAID (Redundant Array of Independent Disks, originally Redundant Array of Inexpensive Disks) is a data storage virtualization technology that combines multiple physical disk drive components into one or more logical units for the purposes of data redundancy, performance improvement, or both.

If you want a STEM topic mangled, have a Liberal Arts major explain it.

[Re 'redundant array of inferior disks': STEM guys make the world go 'round, and are good at analysis. But sometimes fail to detect attempts at humor. ;-) --Mike]

[Neal Elward]

My philosophy is to optimize my backup and restore strategy, and then run the fastest hardware that I can afford, short term risks ignored. My active photo library is currently on an SSD RAID 0 volume.

Many RAID 1 configurations can leave you stranded during a failure unless you have a spare drive on hand. With even a basic backup strategy, RAID 1 isn't going to help much in workstation use and can give a false sense of security.

[Speed]

Microsoft OneDrive has an interesting feature I learned about a couple of months ago.

After I deleted some files I received an email from "OneDrive". It had noticed that I deleted a lot of files and asked if this was on purpose or by mistake. If it was a mistake I could recover them any time over the next 30 days.

This is probably not a Microsoft-only feature.

[Peggy C.]

Not sure, but I think we had the backup conversation in early 2018. I wrote a rather long message on how I do my backups after having had a 5 month old new computer HD failure.

I won't rewrite all of that. Short and sweet...10 2TB internal HDs used externally with 2 separate docking stations, 2 2TB external USB HDs. (Prices of hard drives are dropping all the time).

I run a dual boot Windows/Linux system. Though, I admit, I spend much more time on the Windows side.

First of each month, 2 HDs make full backups of my computer, one after another. Each night for the month they make incremental backups of anything new. Multiple times a day, a single external drive "sniffs" around and makes copies of any new files. Once a month, I make 2 full clones of the computer HD. With the clones I can unplug a dead drive and plug in the clone and be back up and running in minutes.

On the last night of the month, each HD is swapped out for the next set and the process begins again.

All HDs are tested to be sure they do work. I use Macrium Reflect but there are other programs out there that can do the same.

Like my older brother always tells me, "You can never have too many hard drives."
I even keep a few HDs formatted and in reserve in case any one drive decides it's had enough of this earthly realm and wants to leave it all behind. :D

Wow, 'short and sweet' turned out longer than I planned. Sorry.

[Bruce Alan Greene]

My sad lesson about Time Machine...

I had a drive failure, but had a Time Machine backup. I plugged the back up drive (which was pretty full) into my computer and directed it to copy all my lost material.

I came back a few hours later only to discover that the copying was aborted due to the Time Machine set to automatic back up. And, since the back up drive was rather full, Time Machine deleted the oldest backup to make room for the new one, without the lost photographs.

When I returned, I had a new back up and all my lost photographs had been deleted from the back up drive!!!!!!

So the lesson here is: Never never set Time Machine to auto back up!!!! Do manual Time Machine back ups only.

It took me the better part of a week to find almost all the deleted photographs from various older drives. But, one 2 month period did not exist on the older drives. I recovered some of these by using recovery software, but 2 or 3 important images were lost, at least in their original form. I did find some high res .jpgs for these, but not quite what I wanted.

So, if it is truly important, always have 2 or better, 3 back ups, with one off site.

Signed,
Regretful

[hugh crawford]

My life in IT makes me despise raid , and the unreadable raid sets in my personal collection don’t help one bit. But I think others have said it more elequently than I can, so allow me to dump on western digital.

Western Digital external drives have some failure modes that have made me abandon them. The drives themselves are pretty good, but the enclosures fail without any warning and it turns out that the drives are encrypted with a key specific to the enclosure. It does nothing to make the drive secure but renders an otherwise fine drive unreadable when removed from the enclosure or if the enclosure fails.
https://support.wdc.com/knowledgebase/answer.aspx?ID=15150

Too bad because the drives themselves are excellent.

[Rob Campbell]

https://m.youtube.com/watch?v=qrRRhoS3KFk

We had it, then we blew it.

Rob