Using a 1 TB USB hard drive

[ivan]

I agree with Doug. 

I have three computers with two or more 1.5TB drives each in them (all running WSeB CP2).  All of these drives are SATA and I am using the latest Dani driver in each case.  The first drive on each box is internal (one has a second internal drive) and the remainder of the drives are in removable SATA caddies.  I also have several 1TB, 1.5TB and 2TB drives that get slotted into a USB/SATA adapter for use as necessary.

In no case have I had anything than the standard OS2DASD.DMD line in config.sys and, like Doug, all I did for the USB drives was to clear the MBR region with DFSee and use DFSee to make the partitions.  They just work!

I do remember several years ago that we had a client that added a 650GB IDE drive to one of his systems then brought it to us because they were having problems.  All we did was replace the IBM1S506.ADD with DANIS506.ADD.

As far as I know the IDEDASD options only apply to IDE drives and when using the IBM1S506.ADD driver.
 

[Neil Waldhauer]

I read the readme for OS2DASD, and IBM documented the parameters as Ian had outlined. So I'd assume they work unless proven otherwise.

The CHS on my drive was not one that OS/2 could use. I changed it in DFSee.

As for ejecting, I probably used command line, but the USB widget in eCS 2.2 beta 2 is somewhat improved, so that may have worked, too. Either way, with a bad CHS, neither eCS nor DFSee could see the full size of the drive.

This is about a USB hard drive greater than 512 GB. It's nice that some of you have SATA drives larger than that working. So do I. That's not the issue. At least for this particular drive, a Toshiba 1 TB portable, I've posted a procedure that works.

It still takes a long time to fill a 1 TB drive over USB 2.0...

[Doug Bissett]

I read the readme for OS2DASD, and IBM documented the parameters as Ian had outlined. So I'd assume they work unless proven otherwise.

IBM also documented that there are no parameters (do HELP OS2DASD.DMD, from a command line - at least in eCS 2.1), so I wouldn't put money on it, either way.

It still takes a long time to fill a 1 TB drive over USB 2.0...

It does. I have also got an enclosure with USB 3.0 capability. Of course, it doesn't work with OS/2, yet, but it does work with the one USB 3.0 adapter that I do have, under windows 7 Pro 64 bit. It is about 10x faster, as advertized, but it is still slow, when you are talking about that much data. I use my 1 TB USB 2.0 drive for backups. Since it would probably take a couple of days to do a full restore, I plan to remove the drive from the enclosure, and put it directly in the machine, if I ever need to do that.

An even better device, is an enclosure that is USB 2.0, AND eSATA. You need to shut down to connect/disconnect the eSATA (only VISTA and up will allow hot plugging), but it runs at SATA I speed (a limitation of the enclosure), when you do that.

[Neil Waldhauer]

I read the readme for OS2DASD, and IBM documented the parameters as Ian had outlined. So I'd assume they work unless proven otherwise.

IBM also documented that there are no parameters (do HELP OS2DASD.DMD, from a command line - at least in eCS 2.1), so I wouldn't put money on it, either way.

Your doc (CMDREF.INF) is from 2001, while Ian and I are looking at the readme for the OS2DASD used by eCS dated October 2005. The OS2DASD parameters are newer than the doc you quote.

[Alex Taylor]

The OS2DASD parameters shouldn't be necessary with DANIS506.ADD, which IIRC has some extra logic to handle larger hard disks.

I don't know exactly how USB hard disks are affected, but I've used both 1TB and 2TB external USB hard disks without any special parameters.