What would be a fast shared drive that is compatible with my MBP and iMac?

Well the "best" drive to share would be a NAS device. However, I'm sure that you realize that this would be at the higher end of the cost spectrum as these are stand-alone computers with built-in drives.

If you are open to going this route, I suggest that you look at the Synology NAS offerings.

They also have the Bee-series drives, especially the BeeStation, which may be more of what you are looking for.

Ref: https://bee.synology.com/en-us

If you want to work off the same drive, at the same time, you will need to go with some form of networked storage.

Drives that are directly attached via USB, Thunderbolt, etc. are not meant to be shared, and even if you could hook up two computers to them simultaneously, the computers would act independently and destroy the filesystem and the data on the drives.

There are several ways to set up network-attached storage:

• You could buy a dedicated NAS unit. Those tend to be expensive and capabilities vary quite a bit.
• You could set up an old PC or Mac (like a Mac mini) as a file server for your other machines.
• You could set up one of your Macs as a file server for the other. (To one Mac, the storage would be local … to the other Mac, the storage would appear to be network storage.)
• You could use a commercial cloud service, though the performance of that might not be acceptable given typical home Internet connection speeds.

Yes, all of the DS series would be an excellent choice, but I am led to believe that the OP has a limited budget in mind. Potentially, the Synology base DS Series may be a better fit, like the dual-bay DS223J. Amazon is currently selling them for $189.99 USD (without drives) or $506.12 (6TB).

FWIW, I currently have a DS916+. Got it new back in 2016. It has been completely flawless. It currently has WD "Red" drives, but will eventually replace them with the Synology drive offerings.

@christianjward I suggest you give the Synology's NAS Selector a try to see if it can help you make the decision for getting a NAS easier.

Tesserax wrote:

Yes, all of the DS series would be an excellent choice ... FWIW, I currently have a DS916+. Got it new back in 2016. It has been completely flawless. It currently has WD "Red" drives, but will eventually replace them with the Synology drive offerings.

Interesting lineup, thanks for pointing them out. While I hadn't considered myself to be in the market for a NAS drive, you got me thinking. Are you using WD Red Pro drives (7200rpm, CMR)? And have you ever put an SSD in your DS916+ and if so what make/model SSD and did it make any difference in performance?

christianjward wrote:

Thank you! The BeeStation looks great. I wonder if it would be quick enough in terms of working on files that are on it?

Certainly inexpensive, but there are mixed reviews on BeeStation - here's one that's pretty thorough; and here is a video review. And it contains a slow 5400rpm HDD inside and requires a constant internet connection to operate. Perversely, there is a setting for "local users" but even with that enabled, if there is no internet connection the local users can't even use the 'local connection.'

If you want storage independent of your iMac & MBP, you might consider getting a Mac Mini to set up as a file server (Mac file sharing); add a good external SSD drive (TB or USB-3) to it and you have lots of storage. IMHO, a used 3.2GHz core i7 (Late 2018) model would be great for this purpose.

That said, you could even set up file sharing on your iMac and use it as your file server in addition to your personal use. As for performance, it depends on what you mean by "process large volumes of photos."

I think a Synology DS1522 would be a much better choice, although the bare box itself runs about $700 and you still have to put in your own HDDs or SSDs - but that gives you the opportunity to select good drives.

MartinR brings up some good points. They are primarily the reason I opted to go with a NAS for this purpose, and have no regrets doing so ... even at the additional price point.

However, the suggestion to use an older Mac mini is very valid. I have been using minis for years, currently have a M2 Pro model. They make excellent servers and already have the full Apple ecosystem built-in to make sharing easy.

Note that some files cannot be stored on a NAS.

E.g., if you're using Lightroom Classic, I believe that full-size photo files can be on a NAS, but that the catalog file needs to be on a directly-attached drive. This has to do with the ability to lock files on a directly-attached drive against concurrent modification.

With a NAS, the NAS provides protection against corrupting the filesystem, but doesn't necessarily prevent two clients using the same files from interfering with each other.

MartinR wrote:

Are you using WD Red Pro drives (7200rpm, CMR)? And have you ever put an SSD in your DS916+ and if so what make/model SSD and did it make any difference in performance?

Yes, my NAS is currently equipped with 4 - 4TB WD Red Pro HDDs. They are CMR. I do not use SMR drives for a NAS.

Did not elect to go wth SSDs for three reasons:

1. At the time, large capacity SSDs were just too expensive.
2. I do believe that SSDs are not best suited for this task. At least not what I use my NAS for. I feel that the constant writing to an SSD will "wear them out" faster.
3. From my experience, overall throughput performance is not limited to the drive's read/write speeds, but also to the NAS' SATA bus, & local network connection (In my case, 1Gbps Ethernet). For best network performance, I use both Ethernet ports in Aggregate mode and configured for Jumbo frames.

Tesserax wrote:

1. Yes, my NAS is currently equipped with 4 - 4TB WD Red Pro HDDs. They are CMR. I do not use SMR drives for a NAS.

I can guess why.

For the benefit of others: SMR drives are a really bad idea for use in a NAS.

On a SMR drive, when you overwrite old data, you often are destroying other data that you want to keep. (Flash memory used in SSDs has a similar problem). The workarounds needed to paper this over hurt performance. In the specific case where a drive in a RAID has failed, and you have put in a replacement SMR drive, the SMR drive can make rebuilding take so long that there is a much greater chance of another (fatal) failure before the rebuild can complete.

Tesserax wrote:

3. From my experience, overall throughput performance is not limited to the drive's read/write speeds, but also to the NAS' SATA bus, & local network connection (In my case, 1Gbps Ethernet). For best network performance, I use both Ethernet ports in Aggregate mode and configured for Jumbo frames.

Thanks, that's exactly why I asked if you were using SSDs and if they made any difference! The NAS itself also has some overhead.