Sorry for the long post but lots to go over here about using external SSD’s for startup drives and RAID with both Intel and M1 Macs.
Brief history. I do a lot of photography and have been using RAID setups for my data storage since 2012 when I got my 2012 Mac Pro that had 4 internal Sata drive slots inside. Put 4TB drives in each and had a built in 8TB RAID with a 8TB internal RAID backup, plus had an external RAID box for a 2nd backup. In 2015 I put a internal Sata SSD on a PCI-e card and used it for the startup drive. Kept this until 2019 when I switched to a 27” iMac with a 512GB internal SSD and bought external USB RAID boxes with multiple drives for storage and backup. My entire home folder was installed on the RAID boxes, the 512GB SSD held only the system files and my Lightroom catalog and preview files.
So this summer the wife and I were going to Thailand for couple of months and I was worried about going without having a copy of ALL my files with me, from my now, 12TB RAID. I did buy a new 14” MBP M1 Mac Pro for the trip but in the time I had to get it, I could only find the 1TB internal SSD version in stock. So I bought an Acacis TB3 enclosure and put a Samsung 2TB 980 Pro NVME drive in it, total cost about $360, and it’s R/W speeds are in the 2,7000-2,850 MB/s range, very fast, a tiny bit faster than the internal iMac SSD. I used my iMac to install Monterey 12.4 on it and tested this to boot up my iMac and it worked fine, but it ran a bit hot, so I put an external finned heatsink on the enclosure, see photo.
My solution for carrying all my data was to get 3 SanDisk Extreme V2 4TB SSD’s, with R/W transfer rates at (theoretical) 1,050MB/s. I put about 11.5TB total of data files on these and was good to go and used this setup to work on my LR catalogs. But during the trip the Macs M1 1TB internal SSD was limiting, as I initially put too much of my Home folder stuff on it. Lightroom runs a LOT faster if you put the catalog, previews and cache files on the same SSD with the system, and these amount to about 320GB (with the 7 TB of actual photos on the external SSD drives). So I tried to use the Acacis drive with the iMac OS as a startup drive, but it would not boot up it kept saying to reinstall the system. I reinstalled the OS using the MBP M1 and it did start up and put my LR catalog files on it, and used it for my startup drive. All was great and LR worked really fast on the MBP M1, just instantaneous for most processes. This is point #1, yes you can run a M1 Mac off an external SSD, but you need the proper OS versions for M1 Macs (see point #3) to make it work.
Point #2 is concerning external SSD speeds and RAID. The SanDisk Extreme V2 4TB actually run pretty close to the rated speed, I was getting 900-950MB/s R/W via TB4 cables attached directly to the TB4 ports of the MBP M1. This is 3 times my HDD RAID setup at home. But I read about pairing up 2 of them and making a 8TB RAID setup and did so before leaving using Disk Utility. The R/W speeds just about doubled to 1,800-1,850 R/W speeds, but you need to have a separate cable and available TB port for each. Luckily the MBP M1 Pro has 3 TB4 ports so this worked just great, even with the Acacis enclosure as the startup drive. It is amazingly fast to copy huge folders at 6 times the normal HDD RAID setup speed. Minutes instead of hours. Anytime I travel the MBP M1 and 8TB RAID tiny setup will be with me for my photography.
When I got home from our trip I was excited to try the Acacis 2TB enclosure (now installed from my MBP) on my iMac, and this is the 3rd point. M1 Macs (Apple SOC) use a different type of file structure than Intel Macs. My iMac would not startup off the Acacis drive, even though both are the same version of OS and formatted as APFS, it wanted me to reinstall a new copy of Monterey. So last month I bought a Samsung T7 2TB drive (1,050MB/s rated) for only $170*, prices have plummeted over the summer on external SSD’s, and put the iMac system and LR files on it. All works just great. And No, the Samsung startup SSD will not startup the MBP M1 Mac either. You MUST have a system specific OS (Intel or SOC) for an external drive to work.
Really there are no drawbacks to working off an external SSD drive except for startup times on Intel Macs. With my MBP M1 Mac internal 1TB startup is 14 seconds, it only adds 2 seconds (16 total) to startup from the 2TB Acacias enclosure. However the iMac is not so fast, it takes 30 seconds to startup off the internal 512GB SSD but the Samsung 2TB takes and additional 30 seconds, no doubt because it is working at USB 3 speeds. However I did not notice any slowdown at all working with LR or other app and using the Samsung TB SSD as the startup drive. But remember now with the added space I have my LR catalog, preview and cache files with the OS on the external SSD.
Point # 4 is with the new SOC Macs, unless you want to run off an external SSD, you need to get enough storage on the internal SSD to begin with. For me about 1.5TB of space covers everything I want readily available including my LR catalog, preview and cache files, so in the future I will get a 2TB internal SSD. Apple is still charging exorbitant prices for larger SSD’s, just crazy prices, as I just bought this week a 2TB NVME Samsung T7 for $149! With Apple 2TB is $600 more than the 512GB base.
Final point is to use high quality cables, I bought 3 new TB4 cables that are a bit stiffer and thicker for about $22 each. Zero issues with these versus the mess I had initially with the supplied short SSD cables from SanDisk or other ones USB-C one I previously had.
* This was for the standard Samsung 2TB version with all metal case. The Shield version, which is water-resistant and has a rubber outer shell is usually $100 more put I got one this week for only $149 during a pre-Black Friday sale. WOW!
Top Left 2TB Samsung 980 Pro in Acacis enclosure with added heatsink. Middle standard Samsung 2TB T7. Right Samsung 2TB T7 Shield. Bottom 4TB SanDisk Extreme V2, total 12TB. The 2 on the left are a 8TB RAID setup.
Brief history. I do a lot of photography and have been using RAID setups for my data storage since 2012 when I got my 2012 Mac Pro that had 4 internal Sata drive slots inside. Put 4TB drives in each and had a built in 8TB RAID with a 8TB internal RAID backup, plus had an external RAID box for a 2nd backup. In 2015 I put a internal Sata SSD on a PCI-e card and used it for the startup drive. Kept this until 2019 when I switched to a 27” iMac with a 512GB internal SSD and bought external USB RAID boxes with multiple drives for storage and backup. My entire home folder was installed on the RAID boxes, the 512GB SSD held only the system files and my Lightroom catalog and preview files.
So this summer the wife and I were going to Thailand for couple of months and I was worried about going without having a copy of ALL my files with me, from my now, 12TB RAID. I did buy a new 14” MBP M1 Mac Pro for the trip but in the time I had to get it, I could only find the 1TB internal SSD version in stock. So I bought an Acacis TB3 enclosure and put a Samsung 2TB 980 Pro NVME drive in it, total cost about $360, and it’s R/W speeds are in the 2,7000-2,850 MB/s range, very fast, a tiny bit faster than the internal iMac SSD. I used my iMac to install Monterey 12.4 on it and tested this to boot up my iMac and it worked fine, but it ran a bit hot, so I put an external finned heatsink on the enclosure, see photo.
My solution for carrying all my data was to get 3 SanDisk Extreme V2 4TB SSD’s, with R/W transfer rates at (theoretical) 1,050MB/s. I put about 11.5TB total of data files on these and was good to go and used this setup to work on my LR catalogs. But during the trip the Macs M1 1TB internal SSD was limiting, as I initially put too much of my Home folder stuff on it. Lightroom runs a LOT faster if you put the catalog, previews and cache files on the same SSD with the system, and these amount to about 320GB (with the 7 TB of actual photos on the external SSD drives). So I tried to use the Acacis drive with the iMac OS as a startup drive, but it would not boot up it kept saying to reinstall the system. I reinstalled the OS using the MBP M1 and it did start up and put my LR catalog files on it, and used it for my startup drive. All was great and LR worked really fast on the MBP M1, just instantaneous for most processes. This is point #1, yes you can run a M1 Mac off an external SSD, but you need the proper OS versions for M1 Macs (see point #3) to make it work.
Point #2 is concerning external SSD speeds and RAID. The SanDisk Extreme V2 4TB actually run pretty close to the rated speed, I was getting 900-950MB/s R/W via TB4 cables attached directly to the TB4 ports of the MBP M1. This is 3 times my HDD RAID setup at home. But I read about pairing up 2 of them and making a 8TB RAID setup and did so before leaving using Disk Utility. The R/W speeds just about doubled to 1,800-1,850 R/W speeds, but you need to have a separate cable and available TB port for each. Luckily the MBP M1 Pro has 3 TB4 ports so this worked just great, even with the Acacis enclosure as the startup drive. It is amazingly fast to copy huge folders at 6 times the normal HDD RAID setup speed. Minutes instead of hours. Anytime I travel the MBP M1 and 8TB RAID tiny setup will be with me for my photography.
When I got home from our trip I was excited to try the Acacis 2TB enclosure (now installed from my MBP) on my iMac, and this is the 3rd point. M1 Macs (Apple SOC) use a different type of file structure than Intel Macs. My iMac would not startup off the Acacis drive, even though both are the same version of OS and formatted as APFS, it wanted me to reinstall a new copy of Monterey. So last month I bought a Samsung T7 2TB drive (1,050MB/s rated) for only $170*, prices have plummeted over the summer on external SSD’s, and put the iMac system and LR files on it. All works just great. And No, the Samsung startup SSD will not startup the MBP M1 Mac either. You MUST have a system specific OS (Intel or SOC) for an external drive to work.
Really there are no drawbacks to working off an external SSD drive except for startup times on Intel Macs. With my MBP M1 Mac internal 1TB startup is 14 seconds, it only adds 2 seconds (16 total) to startup from the 2TB Acacias enclosure. However the iMac is not so fast, it takes 30 seconds to startup off the internal 512GB SSD but the Samsung 2TB takes and additional 30 seconds, no doubt because it is working at USB 3 speeds. However I did not notice any slowdown at all working with LR or other app and using the Samsung TB SSD as the startup drive. But remember now with the added space I have my LR catalog, preview and cache files with the OS on the external SSD.
Point # 4 is with the new SOC Macs, unless you want to run off an external SSD, you need to get enough storage on the internal SSD to begin with. For me about 1.5TB of space covers everything I want readily available including my LR catalog, preview and cache files, so in the future I will get a 2TB internal SSD. Apple is still charging exorbitant prices for larger SSD’s, just crazy prices, as I just bought this week a 2TB NVME Samsung T7 for $149! With Apple 2TB is $600 more than the 512GB base.
Final point is to use high quality cables, I bought 3 new TB4 cables that are a bit stiffer and thicker for about $22 each. Zero issues with these versus the mess I had initially with the supplied short SSD cables from SanDisk or other ones USB-C one I previously had.
* This was for the standard Samsung 2TB version with all metal case. The Shield version, which is water-resistant and has a rubber outer shell is usually $100 more put I got one this week for only $149 during a pre-Black Friday sale. WOW!
Top Left 2TB Samsung 980 Pro in Acacis enclosure with added heatsink. Middle standard Samsung 2TB T7. Right Samsung 2TB T7 Shield. Bottom 4TB SanDisk Extreme V2, total 12TB. The 2 on the left are a 8TB RAID setup.
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