Who knows about older (DOS era) computers? Need to upgrade/back up old machine

[Corporate666]

One of the items on my to-do list is to back up some computers around the shop that are connected to industrial machinery.  One of those computers is a Compaq DeskPro.  I can't find a part number for the computer itself, but the motherboard part number is 401963-001.  I can't really find a manual for the motherboard, but it has a celeron processor, 2 USB ports, and 3 ATA drive sockets on the motherboard.

My goal is to firstly implement a backup solution.  I don't necessarily need something bomb-proof... I am more a fan of "if it's quick and easy, you're more likely to do it".  This machine doesn't have data that changes much at all, so backups twice a year would be fine.  The computer isn't connected to any sort of network.  I'd also like to pick up a few parts to throw on the shelf just in case anything went wrong since the parts are *so* cheap, especially if you buy them when you don't need them.

Questions:

1) I recall there were limitations on how big of a hard drive older computers could see or use.  This currently has a 4.3GB Maxtor HDD in it.  The type that has a Master/Slave/Cable Select jumper on it.  If I am right (and I might not be) if you buy too big of a drive, an older machine just won't use the extra capacity but the drive will work.  Does anyone remember what the limit is for those older machines? 

2) Does anyone have a recommendation for a cheap and reliable drive?  This machine runs DOS and a custom industrial control (DOS based) application and has maybe 50 data files on it - that's it.  I doubt there is even a couple hundred megabytes of data.  But I'd like to pick up a cheap compatible hard drive to throw on the shelf in case the one in this machine dies.

3) I want to implement some sort of backup solution.  Again - I'm a huge fan of "if it's easy, you'll actually do it".  The USB ports are on the back of the computer and when the computer is installed in the industrial machine, only the front is visible.  I was thinking of permanently connecting a USB flash drive to one of those ports and installing a DOS driver and then occasionally just copying everything from the C drive over to that flash drive so I have a copy in case the HDD failed.  Then I was thinking of getting some sort of 5.25" drive I can install in the front panel below the floppy drive and which would connect to the open ATA port.  I was thinking of just using an Iomega JAZ drive.  They are cheap and would easily take the whole contents of the hard drive.  They are fast too - I *think* they are available as an ATA internal format.  That way I could make a few copies, keep one at work and take one home for an off-site backup.  I know JAZ drives aren't rated for long-term archival storage, but again - not looking for bomb-proof solutions that will survive the apocalypse here... more just a couple of layers of redundancy.   

Any comments or alternative suggestions?  I know there are DAT drives and such - but anything that requires sitting down and loading a program and waiting some long period of time just isn't likely to get done.  A JAZ drive is very quick and could easily copy the whole C: drive with a batch file prior to shutting the machine off once in a while.  Any other suggestions (like some sort of front-panel mount USB solution?  Or something else?) - I'm all ears!

Thank'y.

[dexters_lab]

replacing the HDD with a compact flash card would probably suffice

you can get CF adaptors to do this for peanuts on ebay

[Zero999]

Is flash more reliable than a mechanical hard drive? I've heard differing reports and I'm not convinced either way.

I believe DOS is more of a limitation, than the BIOS, as far as hard drive size is concerned. Installing a larger hard drive and creating a small partition should work, but you'll probably need to use another program, than the default DOS installer. Another thing you could consider is upgrading to FAT32 and MS-DOS 7 (the DOS part of Windows 95 to ME) or FreeDOS, but you'd need to ensure it plays nicely with the software first.

DOS pre-dates USB, by a long shot. I think it's likely that machine has already been upgraded, from the original hardware, which quite likely had no USB ports.

How about putting a USB drive in the back, installing a driver and using a batch file to back up to it, every so often? I suppose the flash drive would still need to be replaced and copied to another computer or stored on the Internet, periodically.

[dexters_lab]

Is flash more reliable than a mechanical hard drive? I've heard differing reports and I'm not convinced either way.

as long as the software isn't writing to the drive all the time then it will be fine.

I wouldn't trust a CF card to run windows though

[Ian.M]

Old Jaz drives are horribly unreliable and when they go bad, typically trash any cartridges you attempt to write to.  As production ceased in 2002, any used or N.O.S. Jaz drives are at least 16 years old and I wouldn't trust them further than I could p!ss upwind in a category 5 hurricane!

You are going to run into serious trouble with DOS's drive size limits, especially if you are running an earlier DOS version.  IIRC the maximum size for a FAT16 partition is 2GB under DOS 6.xx upwards, and FDISK will barf if the drive is over 8GB.   WIN98 SE DOS mode and FDISK using FAT32 are more forgiving - you've still got a limit, but with the correct patches installed its 128GB.

I'm leery about DOS USB mass storage drivers - its can be difficult to get them working stably, they take up a *LOT* of RAM and you'll still have problems with the DOS drive size limits.

As 1GB to 4GB CF cards are still readily available, consider using a CF to IDE adapter.

It may actually be easier to network the old PCs using  MS Network Client Version 3.0 for MS-DOS using the NetBEUI protocol to a Windows server which gives you full DOS access with 8.3 names to a Windows share and can also be used in host mode to share the DOS machine's drive.  As the last Windows version with NetBEUI support was Vista, the best option for the server is WinXP or WinFLP with the PosREADY hack to get updates.    Another option would be a scriptable FTP client (probably using packet drivers, over TCP/IP) to a FTP server on your LAN running under any modern OS.

Its critically important that you keep a working floppy drive + tested boot disks for your DOS version with SYS, FDISK and FORMAT on them (and preferably CHKDSK as well).  Otherwise if the drive goes bad you may have a world of grief making a replacement drive DOS bootable.  If all else fails, its possible to get there with boot disk image files mounted to a VM and an IDE drive dedicated to the VM, but that's a rabbit hole you really don't need to go down.

[medical-nerd]

Hiya

Why not use an option that was available then and can still be done now - a scsi card, a dlt7000 drive and a 35Gig tape with veritas backup or a DOS solution. The scsi card must be matched to the drive requirements - LVD, HVD. The drives are still inexpensive and the tapes have a 30+ year lifetime.

Cheers

[Corporate666]

replacing the HDD with a compact flash card would probably suffice

you can get CF adaptors to do this for peanuts on ebay

Huh, I didn't even think of that... I recall now that laptop drives are essentially pin compatible with CF cards and IDE/CF is pretty much the same interface, so your solution seems like the right one.

I just went on Amazon and found a couple of IDE/CF adapters, one internal and a 5.25" bay mount... so I should be able to install one and copy everything from the existing drive, then pull the original drive and throw it on the shelf as a backup, and install the second CF adapter and use that to occasionally copy everything from the first to the second so I have a backup.  That will give me nice redundancy I think... two CF adapters in case one goes bad and I can easily have a few of the cards around that are byte-by-byte copies of the one in the machine that could be plugged in and get me back up and running in case of problems.

Thanks for the suggestion!

[Corporate666]

Old Jaz drives are horribly unreliable and when they go bad, typically trash any cartridges you attempt to write to.  As production ceased in 2002, any used or N.O.S. Jaz drives are at least 16 years old and I wouldn't trust them further than I could p!ss upwind in a category 5 hurricane!

You are going to run into serious trouble with DOS's drive size limits, especially if you are running an earlier DOS version.  IIRC the maximum size for a FAT16 partition is 2GB under DOS 6.xx upwards, and FDISK will barf if the drive is over 8GB.   WIN98 SE DOS mode and FDISK using FAT32 are more forgiving - you've still got a limit, but with the correct patches installed its 128GB.

I'm leery about DOS USB mass storage drivers - its can be difficult to get them working stably, they take up a *LOT* of RAM and you'll still have problems with the DOS drive size limits.

As 1GB to 4GB CF cards are still readily available, consider using a CF to IDE adapter.

It may actually be easier to network the old PCs using  MS Network Client Version 3.0 for MS-DOS using the NetBEUI protocol to a Windows server which gives you full DOS access with 8.3 names to a Windows share and can also be used in host mode to share the DOS machine's drive.  As the last Windows version with NetBEUI support was Vista, the best option for the server is WinXP or WinFLP with the PosREADY hack to get updates.    Another option would be a scriptable FTP client (probably using packet drivers, over TCP/IP) to a FTP server on your LAN running under any modern OS.

Its critically important that you keep a working floppy drive + tested boot disks for your DOS version with SYS, FDISK and FORMAT on them (and preferably CHKDSK as well).  Otherwise if the drive goes bad you may have a world of grief making a replacement drive DOS bootable.  If all else fails, its possible to get there with boot disk image files mounted to a VM and an IDE drive dedicated to the VM, but that's a rabbit hole you really don't need to go down.

Yep, I keep some bootable disks around for this very reason - been there, done that

Networking isn't really important for this machine, and it's not in a place where it would be convenient either to get a network cable to the machine or to get the network cable inside the machine cabinet and to where the PC is.  It literally just boots into DOS and then runs a clunky DOS program where we select one of several data files that then get sent to the machine and the machine runs. 

Good tip on the CF card size - I was just about to get some 8GB cards... don't need them that big, but I'll keep it to 4GB or less. 

[mariush]

That computer may be limited to using hard drives smaller than 127 GB ... I think another threshold was 512 GB.

The safest best would be to buy one or a couple of cheap 60-120 GB SSD drives. They should work just fine and transparently with an ATA to SATA adapter like this one: https://www.newegg.com/Product/Product.aspx?Item=N82E16812200156

These adapters (the chip on the adapter) probably won't support ssd features like TRIM but as you're not creating a lot of files, the SSD won't need to shuffle data around anyways so there won't need to do TRIM and all that would normally be required on a SSD with high usage, therefore it's not really a big issue.

Yeah, like Ian.M says, you'd probably have to create partitions and make them under something like 32 GB (if you use FAT32 for Windows 95/98) or I think under 8 GB for FAT16

I'd just make a disk image of your whole drive  for backup purposes.

Other than the hard drive, i see as a concern just the power supply. May want to open it up and maybe replace the fan with a new high quality one,  and while you're there check the existing capacitors to see if they're still within acceptable parameters.


Check youtube channels like Phil's Computer Lab  https://www.youtube.com/channel/UCj9IJ2QvygoBJKSOnUgXIRA

He does a lot of vintage pc, dos / windows videos, and he has some videos with ms-dos software and utilities for accessing internet and transferring files over network from dos, i remember seeing a video on his channel about internet/network stuff ... let me see if i can find it ...

Yeah, here's one of them :

[Corporate666]

Hiya

Why not use an option that was available then and can still be done now - a scsi card, a dlt7000 drive and a 35Gig tape with veritas backup or a DOS solution. The scsi card must be matched to the drive requirements - LVD, HVD. The drives are still inexpensive and the tapes have a 30+ year lifetime.

Cheers

I just know that would fall into the "if it's not easy to do, I know I won't do it" realm.  Right when I was out of university, I worked as a systems admin and did backups with DLT tapes and it was just a PITA... clunky software, the tapes were slow to erase and slow to write.  It would be one of those "ehhhh, I'll do it next week" that never happens type of things.  You're right about the longevity of the tapes of course, but I think I'll upload an image of the existing drive to my network which I have an online/offsite backup service backing up nightly... then I can do the CF thing and have 2 drives in the machine and a couple of extra cards to keep in my desk draw at home and at work.

[TopLoser]

I have dozens of old DOS systems working with IDE/CF adaptors and 2GB CF cards. Anything above 2GB is a waste. I do an image backup of the cards on a Windows PC using Acronis, never been let down so far. Trying to make a clean CF bootable using FDISK and FORMAT on the destination PC is sometimes a bit of a nightmare, but just restoring a bootable system to the card using Acronis on a Windows PC always works.

I use Sandisk Extreme III cards, never had one fail.

Oh and those FDD/USB adaptors are good as well, chuck 3.5” media in the bin forever as they let you boot from USB sticks if need be, or to copy daya to/from the PC.

[nctnico]

replacing the HDD with a compact flash card would probably suffice

you can get CF adaptors to do this for peanuts on ebay

Huh, I didn't even think of that... I recall now that laptop drives are essentially pin compatible with CF cards and IDE/CF is pretty much the same interface, so your solution seems like the right one.

I disagree. CF is outdated nowadays. The last few times I upgraded PC based test equipment I bought IDE to mSata (mSata= SATA flash drive with a mini PCI express connector) converter. The converters cost a few dollars from Ebay and they come with a housing which fits right into a 2.5" drive bay.

Another problem with CF is that it identifies itself as a removable disk which may cause boot problems and/or software that won't install on it.

[Stray Electron]

  Unless you need to make a  exact clone of the original drive, the quickest and easiest thing to do would be to use a Lap-Link or Fast-Lynx cable and software to copy all of the data on the drive to another system.  IIRC both programs would still work up though Windows 98 so you could copy any DOS bases system to a W 98 system.  I never tried LL or FL on a newer Win system so I don't know if they will work on those or not.  LL and FL both included two cables, one for RS-232 to RS-232 port and the other for parallel port to Parallel port.  I think the newer versions would also transfer files over a network but I never used that.  I upgraded thousands of old DOS computers to Win 386/486 and Pentium systems though and I never had a problem with LL or FL.  BTW  LL and FL are different products but work the same and will use each others cables so easy-peasy.  BTW2  LL and FL will also work for drive to drive transfers within the same computer.

  Where are you located?

[TopLoser]

All the CPU cards I buy these days come with CF sockets mounted on them. I did try a mSata drive and adaptor once but lost patience with it, BIOS just wouldn’t recognise it. Probably a really old BIOS but it found the CF card ok.

If I could make the mSata drives work I’d use them though.

[Vtile]

If the computer BIOS is that much modern that it can boot to USB, then one "easy" option is to use HDD to USB rack and CloneZilla or some of the commercial disk cloning suites. Even bootable USB stick with CloneZilla might work as bridge solution. I can't recall if the CloneZilla also did run from CD/DVD alone.

[Jwillis]

Why do,t you just get a usb external drive and partion it to smaller vitual drives.Then the computer will just read multiple drives.  USB 3 is  backward compatible. to USB 1.1

[Nusa]

What version of DOS are we talking about? The "ver" command should tell you what's installed.

[Bicurico]

May I sugest replacing the old computer with a virtual machine? If the equipment is connected to your old PC by RS232 then there is no problem. If it uses ISA cards then I seriously advise you to get a whole replacement PC and not just a HDD replacement.

Regards,
Vitor

[jasonbrent]

May I sugest replacing the old computer with a virtual machine? If the equipment is connected to your old PC by RS232 then there is no problem. If it uses ISA cards then I seriously advise you to get a whole replacement PC and not just a HDD replacement.

Regards,
Vitor

This was going to be my suggestion as well... if you have it virtualized, you've "future proofed" it.

[shteii01]

Ok, I have read so far: cf, usb sticks, ssd, backup over the network, and even ZIP drives.

The only thing I have not seen is... CDRW.  Do you have one sitting around?

[David Hess]

1) I recall there were limitations on how big of a hard drive older computers could see or use.  This currently has a 4.3GB Maxtor HDD in it.  The type that has a Master/Slave/Cable Select jumper on it.  If I am right (and I might not be) if you buy too big of a drive, an older machine just won't use the extra capacity but the drive will work.  Does anyone remember what the limit is for those older machines?

2) Does anyone have a recommendation for a cheap and reliable drive?  This machine runs DOS and a custom industrial control (DOS based) application and has maybe 50 data files on it - that's it.  I doubt there is even a couple hundred megabytes of data.  But I'd like to pick up a cheap compatible hard drive to throw on the shelf in case the one in this machine dies.

You can lookup the various limits up online so I will not repeat them here.  A good alternative is to use an IDE to Compact Flash adapter with a standard low capacity Compact Flash card replacing the hard drive.  The Compact Flash interface is the same as the IDE interface so the adapter is just a physical adapter for the connectors without any electronics except for a power connection.  In practice it can be just a small adapter board which allows the Compact Flash card to plug directly into the IDE port.

They also make IDE adapters for other flash memory cards like SD cards but they are necessarily more complex.

3) I want to implement some sort of backup solution.  Again - I'm a huge fan of "if it's easy, you'll actually do it".  The USB ports are on the back of the computer and when the computer is installed in the industrial machine, only the front is visible.  I was thinking of permanently connecting a USB flash drive to one of those ports and installing a DOS driver and then occasionally just copying everything from the C drive over to that flash drive so I have a copy in case the HDD failed.  Then I was thinking of getting some sort of 5.25" drive I can install in the front panel below the floppy drive and which would connect to the open ATA port.  I was thinking of just using an Iomega JAZ drive.  They are cheap and would easily take the whole contents of the hard drive.  They are fast too - I *think* they are available as an ATA internal format.  That way I could make a few copies, keep one at work and take one home for an off-site backup.  I know JAZ drives aren't rated for long-term archival storage, but again - not looking for bomb-proof solutions that will survive the apocalypse here... more just a couple of layers of redundancy.

My solution when using a Compact Flash card to replace old IDE hard drives is to manually backup the Compact Flash card using another system.  There are 5.25", 3.5", and rear mount slot adapters which allow access to the Compact Flash card without disassembly but this grants access by anybody to the Compact Flash card which may not be desirable.

Is flash more reliable than a mechanical hard drive? I've heard differing reports and I'm not convinced either way.

I know typical consumer grade Flash memory is not reliable.  My tests show that USB Flash drives tend to "forget" within a year due to poor retention whether powered or not if they are not periodically rewritten.  Read scrubbing may solve this but I have not tested it.

"Industrial grade" Compact Flash cards are available from companies like Transcend and I have some consumer grade SLC Compact Flash cards from them which have been running FreeBSD for years.  There are also IDE/PATA Flash memory drives but I think a Compact Flash card in an adapter is easier to work with.

Trying to make a clean CF bootable using FDISK and FORMAT on the destination PC is sometimes a bit of a nightmare, but just restoring a bootable system to the card using Acronis on a Windows PC always works.

I do not remember now why I did not have this problem however good Compact Flash cards come with a utility to configure them as removable or fixed if necessary.