Can I use dds4 tape on dds3 tape disk?

[Steve_393]

Can I use dds4 tape on dds3 tape disk?

thanks

[Mark Grant]

Sadly not.

[G. Vrijhoeven]

HI,

No, it is only backward compatible. So DDS4 drive can read DDSn tapes.

HTH,

Gideon

[Stefan Farrelly]

You can, with a bit of work. You need to create a special driver on your server with the DDS4 drive using the mksf command. Then write to the tape using the new device file you created, then you can use the tape in a DDS3 drive.

eg.

mksf -H -b DDS3 /dev/rmt/

Where is the path of your DDS4 drive and is something like /dev/rmt/temp

Then write to your tape using /dev/rmt/temp instead of the normal /dev/rmt/0m

Make sure you use a 125m tape (or 120m).

[Leif Halvarsson_2]

Hi,
Stefan,
Have you tried ?
I am not sure if it will work. The DDS4 and DDS3 medias is physically different and I don't belive the DDS3 drive will accept a DDS4 media.

[Thierry Poels_1]

hi,

Leif is correct, the drive will not accept the tape and will simply eject it.

regards,
Thierry.

[Stefan Farrelly]

If you use a DDS2 (120m) or DDS3 (125m) tape in your DDS4 drive you can write to it aok.
We use 125m (DDS3) tapes in our DDS4 drives and they work perfectly.

[Michael Schulte zur Sur]

Hi Stefan

what you write, seems a bit confusing.
Let me try to clarify it.
You create a new device file on a machine with a dds-4 drive for a dds-3 drive.

This you must of course copy to the machine with the dds-3 drive and this will allow you to use dds-4 tapes in a dds-3 drive.

Have I got you right?

Michael

[Stefan Farrelly]

Hi Michael,

nope. To clarify;

1. You cannot physically use a DDS4 tape (150m) in a non DDS4 drive - it simply gets spat out (regardless of how you wrote to it).

2. If you need to use a tape in a DDS4 drive on a DDS3 or DDS2 drive then my earlier reply is how to do it - use a DSS2 (120m) or DDS3 (125m) tape in your DDS4 drive, create a special device file to write to it, then you can remove it and put in a DDS3 drive and read it fine.

[Michael Schulte zur Sur]

Hi Stefan,

I am still confused. Why the device file?
Why not insert dds-3 tape into dds-4 drive, write, insert dds-3 tape into dds-3 drive and read?
What problems could there be?
Can the dds-4 write someting on a dds-3 tape, a dds-3 drive can't read?

Michael

ps. so the initial answer was of course no!

[Senthil Kumar .A_1]

hello steve,

I perfectly agree with what Michael Schulte has inferred.

Basically there is no forward compatiblity for obvious reason that u may not guess perfectly whats next to come in this case DDS4 is the next technological advance after DDS3.But, there have always been backward compatiblity for supporting previous technology in any field.like hp still supporting hfs.

The dds3 & dd4 catridges may be physically alike to see on the surface.But,there muat be a difference in tape lenght and the capacity of data it can store.

As a rule of temb u can carryon bata backup on DDS1/2/3 using DDS4 DAT drive,also without any special device file to be created.Without offending Stefan Farrelly,I would say that the device file creation is unnecessary.

anyhow as for ur query, the answer is no,because u cannot mount a DDS4 catridge on a DDS1/2/3 DAT drive ,as they are not forward compatible...

[Naveej.K.A]

One more point to note:
DDS1 DATs can't be written using a DDS4 drive. but u can read from a DDS1 dat using a DDS4 drive

regds
Naveej

[Vincent Farrugia]

Hi Michael,
Hello,

"nope. To clarify;

1. You cannot physically use a DDS4 tape (150m) in a non DDS4 drive - it simply gets spat out (regardless of how you wrote to it).

2. If you need to use a tape in a DDS4 drive on a DDS3 or DDS2 drive then my earlier reply is how to do it - use a DSS2 (120m) or DDS3 (125m) tape in your DDS4 drive, create a special device file to write to it, then you can remove it and put in a DDS3 drive and read it fine."

Stefan, this guy needs to read a DDS4 tape into a DDS3 drive. From what you said above (no. 1), no matter what you do, it will get spat out. And I agree with you.

So, NO, you cannot use a DDS4 tape in a DDS3 drive.

HTH,
Vince

[Ralf Loehmann_2]

To clear some confusions, Vincent is right it does not work.
The simply answer here is, the DDS media is responsible in which format the tape drive will write. The only thing you can define with the device file is, if it is written with or without compression. Most drives are backward compatible, but it might not be recommended to use. The reason is that the lower density tape is different in thickness, material, etc, this might results in higher wear on the heads and drive.
Here a WebPages, which shows which media can be used in which drive: http://www.hp.com/products1/storage/products/storagemedia/tape_dds/compatibility.html

I hope it helps to this confusion,
Ralf.

[Joshua Scott]

Confusion abounds.

What Stephan was saying was that a DDS3 tape can be used in a DDS4 Drive. if you follow his instructions, then you can also take that same tape and use it in a DDS3 drive.

You cannot use a DDS4 tape in a DDF3 drive.

Josh

[Michael Schulte zur Sur]

Hi Steve,

maybe you can tell us, if we confused you more or made the issue clear.

thanks,

Michael

[Kevin Hsui]

if i use a dds3 tape in a dds4 drive to backup something files, then i use a dds3 tape drive on diff box to restore the dds3 tape made from dds4 drive. will this work?

kevin.hsui@trizetto.com

[Dave Dewar]

Kevin, yes it will work

The DDS family is backwards compatible, so DDS 4 can write/read DDS4, DDS3 and DDS2 tapes and read DDS1 tapes. When it writes DDS3 tapes it writes DDS3 format, likewise DDS2 etc. Hence a DDS3 tape written in a DDS4 drive can be read by a DDS3 drive and of course a DDS3 tape written by a DDS3 drive can be read by a DDS4 drive.

What a convoluted thread, so easily solved by posting the following link showing DDS tape/drive compatibility.

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?locale=en_US&taskId=120&prodSeriesId=63890&prodTypeId=12169&objectID=lpg50457

Cheers,

Dave Dewar

[D. Melander]

Also, using a larger tape (i.e. 125m) in an unsupported drive can cause mis-alignments in the mech. Not suggested.