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Fitting a SCSI2SD in a 68k Mac

Thanks for your patience. It's been twenty-odd years since I briefly used Mac OS9 before switching to OS X (previously, I always used Amigas, and OS X felt very familiar). I haven't used OS9 (or previous versions) in so long, it's a bit like trying to remember your high school French when stranded in the middle of Paris.

 
Since you have 8.1 working under basilisk, use that as your primary disk (boot), use mine as the secondary.   Delete the system folder off mine.  Copy the 8.1 system folder over, and run system picker to "bless it".   
It works! Mac OS8.1, running happily. Have installed an ethernet card, so I should be able to transfer software over. Might need to reseat the 32Mb Simm I added, as it doesn't seem to be showing up.

Thanks for your help. Couldn't have done it without the guide on your blog (and a little extra help here).

 
Well, it did work. Was going through the hard drive, finding out what was installed and then played a bit of Lemmings. then I got a message onscreen telling me that the Finder couldn't be started, because a particular file couldn't be found and I'd have to restart the Mac from the CD drive by holding down the C key (which as far as I know only works on 'new world' Macs. I couldn't shut down, so I had to power off. Then, I started it up again, and the Mac froze part way through booting, only loading about four extensions. So, I reasoned that must be the problem, and remembered that you can disable extensions to find out what's what. So, I rebooted again, with the shift key held down, which should have disabled them. Then the Mac started displaying a Sad Mac instead. So, I'm back to square one. :(

 

miko-Tokyo

Member
Hello everyone. 
The other day (12/2020), I benchmarked various manufacturers' SD memory cards on my Quadra700 (PPC50Mhz) and FWB JackHammerSCSI with SD2SCSI Version 6:2020. I would like to share the results here. 

I hope this will be helpful for those who are planning to buy SD2SCSI. 
(This text has been translated by Deep-L)

Environment 
Quadra700 
MEM:68MB 
SCSI:JackhummerSCSI 
OS:8.1 Japanese 
Purchased SD2SCSI:http://shop.codesrc.com/ 
SD Memory: 32GB
Trancend
Sundisk
KIOXIA(TOSHIBA)
SAMSUNG
MANSA

1) About SCSI2SD 
First of all, there is a big difference between the latest V6 and the earlier versions. 
V6: Maximum transfer rate 10MB/s 
V5.5: Maximum transfer rate 1MB/s 
V5.0,5.1: Maximum transfer rate 2.3MB/s~2.6MB/s 

Therefore, if you are buying a new one, V6 is recommended. 

Note: However, if you use the internal SCSI, the SCSI itself is slow.
Performance is the same for both V6 and V5.
We do not know why it is so slow.
Maybe it can be changed by adjusting the settings.

For more information 
http://www.codesrc.com/mediawiki/index.php/SCSI2SD#Technical_Specifications
for more information. 

2) Setup 
First, you will need to set up the 
http://www.codesrc.com/mediawiki/index.php/SCSI2SD#Download
to download the setup software. 

If you are using V6, be sure to download the V6 software.
Download the latest firmware along with it. 
Windows, OSX, etc. are supported.

Connect the PC and SCSI2SD via USB.
After downloading, run scsi2sd-util.
(I did this on a Macbook AIR M1)

After launching, the status will be displayed in the lower left corner of the window.
After launching, you will see the status in the bottom left corner of the window, and if it is connected,

it will show firmware version 6.3.1.
Let's upgrade the firmware to 6.3.2 first.

If the menu does not respond at this point, click on another application window, and then try again.
If the menu does not respond here, click on another application window and go back to SCSI2SD_util. It should work.

Select FILE>UPGREADFIRMWARE... and select the firmware you downloaded.
Select the firmware you downloaded and update it. It should finish soon.

Go back to the menu.

In the "General" tab, I set the following
SCSI Speed Sync, 10MB/s
Startup Delay(second) 0
SCSI Selection Delay 255
Enable Parity : ON
Enable Unit Attention : ON
Enable SCSI2 Mode : ON
Respond to short.... Map LUNS to SCSI...: OFF
Map LUNS to SCSI...: OFF
Enable Blind Writes : OFF

Device1" tab
SCSI : 0
Device : Hard Drive(Defaults)
SD card start sector : 0(Defaults)
AUTO : ON
Sector size : 512 (Defaults)
Device size 2GB

The following settings need to be changed when using APPLE standard formatting software.

I used a third party software.
I left it as it is. (HARD DISK TOOLS Kits, Lido, etc.)
Vendo codesrc(Defaults)
Product SCSI2SD(Defaults)
Revision 6.0(Defaults)
Serial number 1234567812345678(Defaults)

Set the "Device2" tab as well, if necessary.
Set the SD card start sector Auto to ON.
The sector count will be automatically set according to the capacity to be allocated.

I tried to set the Deice further, but
In my case, when I set it, the SCSI2SD stopped responding.
This was the same phenomenon even after changing the memory card.
I don't know the cause.

When you have finished setting up
FILE>SAVE to Device
and save the settings to the SCSI2SD.
This setting seems to be saved to the SD card. (I guess).
So, if you replace the SD card, you will need to configure it again.

At this point, the drive you have configured is automatically mounted on your PC.
Please unmount it and then unplug the USB cable.

3) Connecting to Macintosh
Connect the drive to the SCSI cable and turn on the switch.
The formatting and OS setup are omitted.
I used a floppy EMU
https://www.bigmessowires.com/shop/product/floppy-emu-model-c/
and formatted it with Lido 7.6.1.

4) Benchmark
The following is the data I measured with MacBench 3.0.

ーーーーーーー





Disk Tests:



trancent32gb



kioxia



mansa



samsung



sandisk



Power Macintosh 6100/60








Disk Mix:



19.5



16.02



15.6



15.24



15.62



10



score





Publishing Disk Mix:



15.72



14.86



14.53



14.06



13.46



10



score








trancent32gb



kioxia



mansa



samsung



sandisk



Power Macintosh 6100/60








Sequential Read 512:



145



112



106.11



106.57



111.22



141.23



kilobytes/sec





Sequential Read 1K:



259.04



202.38



196.56



194.82



199.71



244.75



kilobytes/sec





Sequential Read 32K:



2570.77



2320.2



2431.79



2432.2



2213.87



2839.59



kilobytes/sec





Sequential Read 64K:



2984.58



2842.24



2933.51



2930.18



2624.18



2838.77



kilobytes/sec





Sequential Read 128K:



3216.92



3124.38



3155.95



3127.23



3036.34



2854.26



kilobytes/sec





Sequential Read 1024K:



3881.62



3681.91



3728.52



3668.93



3447.7



2742.19



kilobytes/sec








trancent32gb



kioxia



mansa



samsung



sandisk



Power Macintosh 6100/60








Random Read 512:



107.43



87.28



81.12



83.35



84.22



26.31



kilobytes/sec





Random Read 1K:



191.53



157.18



149.19



157.78



147.46



50.95



kilobytes/sec





Random Read 32K:



2455.58



2238.15



2275.87



2295.44



2038.71



1095.93



kilobytes/sec





Random Read 64K:



2963.83



2857.8



2904.47



2922.72



2591.06



1579.79



kilobytes/sec





Random Read 128K:



3295.51



3216.7



3213.15



3224.2



3167.76



2001.97



kilobytes/sec





Random Read 1024K:



4052.4



3829.04



3875.82



3871.85



3687.62



2682.66



kilobytes/sec








trancent32gb



kioxia



mansa



samsung



sandisk



Power Macintosh 6100/60








Sequential Write 512:



358.67



356.42



350.23



345.36



349.28



344.93



kilobytes/sec





Sequential Write 1K:



543.02



547.97



540.92



528.86



528.68



461.41



kilobytes/sec





Sequential Write 32K:



1869.34



1876.75



1875.13



1577.53



1646.79



1298.84



kilobytes/sec





Sequential Write 64K:



2084.51



2224.46



2238.85



1905.5



2027.37



1784.55



kilobytes/sec





Sequential Write 128K:



2196.51



2254.81



2290.24



1937.72



2079.31



2191.36



kilobytes/sec





Sequential Write 1024K:



2493.99



2671.35



2433.68



2158.85



2386.58



2566.3



kilobytes/sec








trancent32gb



kioxia



mansa



samsung



sandisk



Power Macintosh 6100/60








Random Write 512:



86.75



70.61



57.48



68.94



75.5



43.45



kilobytes/sec





Random Write 1K:



181.09



164.74



145.13



147.25



165.9



65.01



kilobytes/sec





Random Write 32K:



1722.47



1774.42



1721.24



1647.07



1557.06



1068.41



kilobytes/sec





Random Write 64K:



2065.93



2209.88



1879.95



2077.82



1994.52



1525.85



kilobytes/sec





Random Write 128K:



2235.25



2341.1



1984.36



1949.58



2142.92



1978.69



kilobytes/sec





Random Write 1024K:



2592.2



2735.01



2414.5



2283.68



2441.96



2622.4



kilobytes/sec






ーーーーーーー

Thank you !

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ktkm

Well-known member
Hello everyone. 
The other day (12/2020), I benchmarked various manufacturers' SD memory cards on my Quadra700 (PPC50Mhz) and FWB JackHammerSCSI with SD2SCSI Version 6:2020. I would like to share the results here. 

I hope this will be helpful for those who are planning to buy SD2SCSI. 
(This text has been translated by Deep-L)


Very thorough! I’ve used the Jackhammer together with SCSI2SD v5.1 in a Quadra 950, but didn’t feel I gained anything with the settings I used compared to the built-in bus. How did you configure the Jackhammer?

 

miko-Tokyo

Member
To ktkm

Because the maximum transmission rate of V5 is 2.3MB/s. In this case, there is no change in the Jackhammer or internal SCSI. If you want to get faster, you have to buy SCSI2SD of V6. I also bought a new V6 because the first SCSI2SD version .Perhaps in V5, even if it's good, it's only about 1MB/s.

——————-

V5(Max2.3MB/s) >>JH(Max20MB/s) >>  500KB/s-1.2MB/s

V6(Max10MB/s)>>JH(Max20MB/s) >>3MB/s-10MB/s

———————

By the way

I got new Quadra700 with Nuvista video card at Jank shop in Akihabara,Tokyo. :)

C494F4FF-5DF9-496B-8951-C81AACEFB6E0.jpeg

 

sutekh

Well-known member
Can you provide some specifics about the cards you used from each manufacturer? Recognizing that the flash in most SD cards isn't particularly well suited for continuous rewrite and therefore use in an SSD application, I've been using a mix of Samsung's "Endurance" and Sandisk's "Max Endurance" cards in my SCSI2SDs. They supposedly have embedded controllers that shuffle writes across unused NAND like true SSDs do, but specifics from each mfg are limited. I suspect they're slower as a result, but it's a small price to pay for data integrity IMO. Anyway, I'm curious to know what you tested. Thanks!

 

ktkm

Well-known member
Because the maximum transmission rate of V5 is 2.3MB/s. In this case, there is no change in the Jackhammer or internal SCSI. If you want to get faster, you have to buy SCSI2SD of V6. I also bought a new V6 because the first SCSI2SD version .Perhaps in V5, even if it's good, it's only about 1MB/s.
Its about time I get a v6 to throw at the hammer! Thank you for the benchmarks, and good set-up btw. Nice yellow handles on that bubble-wrapped Q700! :)

 

miko-Tokyo

Member
>>ktkm

Thank you. I'm looking forward to your Quadra to power up. If there's anything you don't know, ask me a question. I also use twitter. Follow me if you like. Have a nice weekend!

@shinjyukukabuki1

 

Trash80toHP_Mini

NIGHT STALKER
What are the transfer rates and durability of Compact Flash in continuous write/rewrite Mode? Might that ancient medium be better suited in a low cost SSD replacement role in even more ancient Macs for Fast/Narrow SCSI II?

Dunno, CF works like a dream in my PCMCIA PowerBooks and Alchemy/Gazelle menagerie on the sloooowwww (if equal to or even a bit better than standard Mac SCSI) first gen Macintosh IDE and PowerBook PCMCIA roles. There is more interesting current tech storage media in the fixed disk role, but the handiness of SD+SCSI seems hard to beat even if beating the snot outta the poor SD Cards.

One day I'll break down and try out a V6 on my Fast/Narrow SCSI cards and Macs with the faster bus.

 

Cory5412

Daring Pioneer of the Future
Staff member
Compact Flash


There aren't any new-built compact flash adapters being built, and the previous one cost more than a scsi2sd v6 does anyway, and the remaining CF media is either uninspiring or costly.

CF itself would be fine for that role, although not really any better than SD, they're very similar types of flash with very similar intended usage scope, and so for random performance and/or long-term longevity, especially with newer and heavier operating systems and workloads, they're going to be about equivalent.

If you're asking about what to do for the handful of roles where SD cards are considered to be unsuitable:

The handful of people whose needs exceed what an SD card can do have already gotten themselves SCA disks. (johnklos, for example, runs BSD builds on Quadras and the longevity of spinning rust that's compatible with these machines is more suitable to that task, especially given the low speed of beige Macs.)

Video, as well, may be a task where you're better off using a period or a newer type of SCSI disk with an adapter.

That said, SCSI2SD v6 with a good SD card is pretty good, here were my tests from the 10MB/sec bus on a PowerMac 8600: 



Basically, about 7.5MB/sec read and ~3.8-4.8 MB/sec write. On OS 9.1, it's perfectly fine for day-to-day, but those write numbers are a little bit short of where, say, macworld recommended people be for video on an 8500 back in the '90s. (Granted: for the 8600, you can just... put a SATA Card in, I haven't done that yet because I didn't have one available for it when I did this testing.)

Recognizing that the flash in most SD cards isn't particularly well suited for continuous rewrite and therefore use in an SSD application, I've been using a mix of Samsung's "Endurance" and Sandisk's "Max Endurance" cards in my SCSI2SDs.


Hmm, what kind of speeds are you getting out of these? I'm presuming it's "good enough", that you keep using them, It's been a long time since I've seen an explicit amount of like, read/write cycles but back in the early 2010s when SSDs were still kind of "new" as a consumer product there was worry about what that would look like, because flash drives from then would kick it after hilariously few rewrites. 

I imagine this would be influenced by the way you use your machine and thus far the only reports (that I can remember) of failed SD cards come from the ~5-or-fewer doing really heavy software development on 68k macs.

 

sutekh

Well-known member
Hmm, what kind of speeds are you getting out of these? I'm presuming it's "good enough", that you keep using them, It's been a long time since I've seen an explicit amount of like, read/write cycles but back in the early 2010s when SSDs were still kind of "new" as a consumer product there was worry about what that would look like, because flash drives from then would kick it after hilariously few rewrites. 

I imagine this would be influenced by the way you use your machine and thus far the only reports (that I can remember) of failed SD cards come from the ~5-or-fewer doing really heavy software development on 68k macs.


TBH, I haven't benchmarked them owing to the fact that, as you surmised, they're "good enough", but I was encouraged to see the Samsung Endurance included in @miko-Tokyo's comparison. While certainly not the front-runner, it's adequate by my SCSI-1 equipped gear's standards and only really falls behind the rest of the pack in random / sequential writes. That would make sense too if those writes are being buffered through a controller with some sort of algorithmic re-mapper or because the "endurance" line uses something like V-NAND vs. MLC. Aside from a higher published MTBF, details about what these cards do and how is limited.

I'll say this though, I've had a number of SD cards fail over the years personally and professionally in high P/E I/O applications, and the virtual memory I regularly use on say, for instance, my 14MB physical capped PB 180c definitely qualifies as high P/E I/O. Times change, flash has gotten better, and I'm probably still jaded by some of the scars I bear from the era you mention, but a few extra $$$ for a more reliable card with a write-speed penalty that doesn't even matter on a SCSI bus too slow to notice seems a small price to pay for data integrity.

A good friend of mine was a hardware engineer at FusionIO (early SSD market leader and now part of SanDisk) for many years, and his anecdotal, unspecific so as not to violate any NDA indication was that their SSDs were built with several times the presented maximum capacity, and the "secret sauce" was really their software algorithms that predicatively anticipated failures and re-mapped behind the scenes. Even these days, the shiny new new 6 and 7 figure NVMe arrays I'm buying today from Pure, HPE, etc. do the same thing, although good luck getting an SE to disclose how and to what extent! Flash is awesome, but I'll never 100% trust it :)

 

Trash80toHP_Mini

NIGHT STALKER
There aren't any new-built compact flash adapters being built, and the previous one cost more than a scsi2sd v6 does anyway, and the remaining CF media is either uninspiring or costly.

CF itself would be fine for that role, although not really any better than SD  .  .  .


Thanks the latter was what I was wondering about. I do have and IDE->SD adapter card to try out alongside my IDE->CF adapters. The former wasn't really about practicability of new-built CF adaptation, really just curiosity. Until current 3.3v solid state memory modules hit a Fast/Wide SCSI II bus it's nothing but theoretical. There wouldn't be any market at all for such unless it takes the form of a new tech NuBus card made in JackHammer's image with n HDD on a card twist. Such would really be something, but even then there wouldn't be much market or point to it unless it fits into the "because I can and really want to" category for someone. SCSI2SD's development and price point strengths lie far outside the RetroMac market.

Data portability makes SD a very enticing notion for CSII era machines that really don't have anywhere to put a CF slot. Filing a bit to notch out a PCI cover plate to loop an SD expansion cable out the slot of TAM or 6360 appeals to me. Has anyone yet tested SCSI2SD with one of those cables? That notion would work with a NuBus backplane plate as well. For that matter, the MicroSD male end of my extension cable inserts into and looks to go right through a security slot. That'd be fine and dandy an internally SCSI modded Plus, but ye olde battery cover exit ploy remains in play. With a few dabs of hot glue the Full SD female end would feel right at home next to either.

Right back on topic, sort of, when fitting-a-scsi2sd-in-a-68k-mac, maybe keep in mind pointing the SD slot to the rear of the Plus or Classic cases in, esp in the case of the Classic that's w/o battery cover possibility. Wouldn't want to yank an extension cable out sideways much less from the front of an SD card slot. :eek: My cable's 18", but no sense enabling a random fecal occurrence during a simple bucket removal

 

Cory5412

Daring Pioneer of the Future
Staff member
.

I'll say this though, I've had a number of SD cards fail over the years personally and professionally


The 2010 thing was a bit of an incomplete thought but I'm having a weird day and the time between me thinking it and me writing it was enough that I lost the thread.

The next thing I think I was going to say was looking at datasheets for ~2010-2011 or so SSDs and calculating, like, what if you rewrote this thing in full constantly until the end of the cited life and, you get something like 50-60 years out of that.

Maybe the connection was: But even as far back as 2010 or 2011 SSDs were being given caches and wear leveling techniques and had internal controllers responsible for spreading writes around and SD cards Don't.

W/re VM on low-memory systems, that's a good point and for my part, the desktops where I've got these things deployed so far don't need VM, but, I also continue to hold firm on the idea that it's not bad to leave VM on even if you don't need it.

W/re scars from earlier eras: me too, in a bunch of ways. At this point, (outside of cameras) I basically don't put anything but like OS installers and the fourth copy of stuff on cheap removable flash if I can avoid it.

At this point my strategies are relentless centralization plus hooking a dedicated spinning backup disk to every machine, or designating a network location (In the case of my modern Macs, that's my '11 mini, in the case of my vintage ones, I store data directly on vtools.)



That would explain why these are hanging around so long in used markets. 

Until current 3.3v solid state memory modules hit a Fast/Wide SCSI II bus it's nothing but theoretical.


If I'm reading this right: The problem isn't the SD or CF cards on their own - those are now rated for more speed than U320 SCSI. It's a combination of the cards not being meant for use in computers, and, the adapters using SPI interface, which is not the fastest possible way to use an SD card.

The primary non-Mac markets don't need much more than what a SCSI2SD - of any kind - will give you, and the presumptive higher-end markets 1) got new SCSI disks manufactured until roughly 2012, perhaps a little later 2) are 100% hobbyist based 3) often, have the same options we do for newer systems, such as SCSI/SAS cards, so they're not considering SD that closely anyway.

Data portability makes SD a very enticing notion for CSII era machines that really don't have anywhere to put a CF slot.


Hmm.

Outside of "well, you literally just mentioned the networking slot, so, use networking" - that sounds like a great use case for the SCSI2SD v5.5. Those can plug in at the back of the Mac.

That said, SD cards when used in the SCSI2SD, because the default configuration for the SCSI2SD is to emulate a hard disk, have the same cross-generational limitations hard disks do. i.e. you won't be able to use HFS+ on system 7 and you won't be able to use >4GB volumes on '030s or with 7.1, so-on-and-so-forth.

So, like, calling back to the networking slot: These things are all problems that networking solves. AppleTalk networking is baked into every Mac from the original to the Beige G3 (and the protocol survived on Ethernet until 10.4), even the Duos, as their only onboard port. Even on an ad-hoc basis, I keep a couple Mac serial cables around so I can do stuff like use a beige desktop to move stuff from vtools to my 180 or 6200, but I also keep an ET/LT bridge at the handy so I don't really need "a bridge mac" to do it, I can talk directly to the file server if I need.

I've got a Classic II with a SCSI2SD set up with 2+2GB volumes (if I remember correctly) and I use it this way. Software is installed on the SCSI2SD and it auto-mounts my folder on vtools and I store my data on the network, so all my other Macs can get at it. The one piece of data on the machine is my Claris Organizer file, which I use locally and sync each session to a central file on the server.

So, in that Mac, the SCSI2SD is just fitted near the existing hard disk, which got left in for reasons I don't remember. Anyway, using networking, even over LocalTalk, is faster and easier than dealing with swapping SD cards around or shutting machines down and powering them back on so I can move a data volume around.

 

Trash80toHP_Mini

NIGHT STALKER
What's a networking slot?  :grin: My bad there, CSII was a dual purpose modem/NIC and now is a single use interface. I used it only as shorthand (dubious, unsatisfactory as it was) for Alchemy thru TAM PCI machines with first gen IDE as it's one of the defining, if overlooked features of the series. They only address one IDE device so something like SCSI2SD might make for a good addition. Put that and a simple CF adapter in the HDD bay and hang the SD card out the back on an extension tether. I now wonder if installing the laptop SCSI2SD inside the now useless Tuner compartment would work. But that's still farther off topic.

.  .  .  sounds like a great use case for the SCSI2SD v5.5. Those can plug in at the back of the Mac.


I did a double take on that one, fitting SCSI2SD onto the outside of a Mac? Then I stepped back and rediscovered the topic's not about physically fitting SCSI2SD in a Mac, it's about getting the things up and running in a 68K environment! Again my bad, you were talking SD suitability/quality/durability/lifespan and I had a side question about CF in comparison. Thanks for your answer.

I did say that the MicroSD male end of my extension cable looks to slip through the Security Slot of a Mac, especially nice for a Plus(internal SCSI upgraded) or Classic if installing SCSI2SD internally. That would keep the data side of things portable, as in swapping out removable media from the extension cable without cracking the case. One might want to use v5.5 shared across several machines, but one or two special machines might have SCSI2SD installed internally. The pet IIfx comes to mind, a dedicated V6 on its Fast/Narrow SCSI Card would be really nice, especially if I didn't have to pop the hood for the likes of an SD oil change. Breaking SD media out of the box on a cabled extension might be great for that? Not so if it's already been tried and found to not work so well? I guess that's for another topic.

I'll be quiet now.

 
Last edited by a moderator:

aperezbios

Well-known member
But even as far back as 2010 or 2011 SSDs were being given caches and wear leveling techniques and had internal controllers responsible for spreading writes around and SD cards Don't.
This isn't an accurate depiction of the current state of things, these days, in all circumstances. Most consumer SD cards do have some form of simplistic wear leveling, although the specifics are considered industry secrets. Many SD cards now exist for custom write-heavy uses, which may have a larger array of pre-reserved blocks for re-allocation later in life, if cells/blocks go bad. And then there are the rather expensive Single Level Cell SD cards, which Panasonic and Delkin Devices, as well as a number of others make. They're costly for a reason.

 

Cory5412

Daring Pioneer of the Future
Staff member
SII was a dual purpose modem/NIC and now is a single use interface


What was the other use?

Dial Up Networking is still, networking, even if it's only wide-area networking and not local area networking.

It would be neat to find out that there was like a CSII sound card or a CSII SATA card.

This isn't an accurate depiction of the current state of things, these days, in all circumstances.


That's good to hear. Do you know if any of them have terabytes written ratings or any kind of indication as to what the expected reliability actually is?

I've been using high end consumer oriented cards and they're fast enough, I'm fortunate to be able to not need VM, although with even basic wear leveling, at the rate older classic Macs go, I imagine that it would be "fine" for a while.

More generally:

I would say a worthy precaution for anybody who is concerned about data loss with a modern disk replacement solution using flash cards would be to run backups, just like you would have if you were concerned about data loss on a conventional/period hard disk.

 
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