On Tuesday 09 August 2005 01:52 pm, Sebastian Jeremias wrote:

Bruce Marshall wrote:

...

All of the DAT drives I've ever used did the compression without being told. Are you sure that isn't the case here?

What makes you think it isn't using compression?

BTW, figure on getting only 1.6 times the data (or less) on the tape when using compression compared to the 2.0 they tell you that you will get.

I'm backing up two partitions. One is 9GB and the other is 11GB. That's MUCH less than 40 :)

And the tape runs out??

What's strange is that even software compression wouldn't make it (either bzlib or zlib, level 5).

What does "wouldn't make it" mean?

But I'll try that again... it sounds almost weird. Most of the files are plain text.

What's the density level I should pass to the dump program to reach DDS-4 density?

In my opinion, nothing.

On Tue, 2005-08-09 at 14:52 -0300, Sebastian Jeremias wrote:

Bruce Marshall wrote:

...

All of the DAT drives I've ever used did the compression without being told. Are you sure that isn't the case here?

What makes you think it isn't using compression?

BTW, figure on getting only 1.6 times the data (or less) on the tape when using compression compared to the 2.0 they tell you that you will get.

I'm backing up two partitions. One is 9GB and the other is 11GB. That's MUCH less than 40 :) What's strange is that even software compression wouldn't make it (either bzlib or zlib, level 5). But I'll try that again... it sounds almost weird. Most of the files are plain text.

What's the density level I should pass to the dump program to reach DDS-4 density?

Thanks a lot

I never changed the density on a tape drive but try man mt, it has more info regarding setting density. I'm guessing that the density has something to do with tape capacity. -- Ken Schneider UNIX since 1989, linux since 1994, SuSE since 1998 "The day Microsoft makes something that doesn't suck is probably the day they start making vacuum cleaners." -Ernst Jan Plugge

On 8/10/05, Sebastian Jeremias wrote:

Ken Schneider wrote:

...

I never changed the density on a tape drive but try man mt, it has more info regarding setting density.

I already tryied nearly all mt options without results... I also installed mtst, that's an "enhanced" (?) version of mt, but I got nothing relevant regarding compression.

...

I'm guessing that the density has something to do with tape capacity.

Me too... that's why I need to know DDS-4 density code to pass to mt, or in bpi, to pass to dump...

Thanks, Sebastian

Have you looked into stinit? You can set compression in the /etc/stinit.def file. I have not experimented with modifying compression via stinit, but that is another thing you can try. FYI: IIRC the package for this is on the DVD, not the CDs. Greg -- Greg Freemyer The Norcross Group Forensics for the 21st Century

On 8/11/05, Sebastian Jeremias wrote:

Greg Freemyer wrote:

...

Have you looked into stinit?

You can set compression in the /etc/stinit.def file.

I have not experimented with modifying compression via stinit, but that is another thing you can try.

FYI: IIRC the package for this is on the DVD, not the CDs.

Greg

I didn't try that because I don't know the density value to pass to stinit. Do you know it?

A quick google comes up with: # My guess for DDS-4 manufacturer=SONY model = "SDT-10000" { scsi2logical=1 can-bsr can-partitions auto-lock mode1 blocksize=0 compression=1 mode2 blocksize=1024 compression=1 mode3 blocksize=0 compression=0 mode4 blocksize = 1024 compression=0 } That is the entry that goes into /etc/stinit.def Mode1 is the default I think. blocksize=0 means it is variable. compression=1 enables compression. (I think more precise densities can be set here also, but make sure you have compression working first.) If you look at your dmesg output after a boot, you should be able to verify the above manufacturer and model match your drive. the above will only have an impact if you have a stanza like above that matches your drive. Then you typically just call stinit with no args. Greg

On Thursday 11 August 2005 10:28 pm, Ken Schneider wrote:

On Thu, 2005-08-11 at 19:32 -0400, Greg Freemyer wrote:

...

On 8/11/05, Sebastian Jeremias wrote:

...

I didn't try that because I don't know the density value to pass to stinit. Do you know it?

A quick google comes up with:

# My guess for DDS-4 manufacturer=SONY model = "SDT-10000" { scsi2logical=1 can-bsr can-partitions auto-lock mode1 blocksize=0 compression=1 mode2 blocksize=1024 compression=1 mode3 blocksize=0 compression=0 mode4 blocksize = 1024 compression=0 }

That is the entry that goes into /etc/stinit.def

Mode1 is the default I think. blocksize=0 means it is variable. compression=1 enables compression. (I think more precise densities can be set here also, but make sure you have compression working first.)

If you look at your dmesg output after a boot, you should be able to verify the above manufacturer and model match your drive. the above will only have an impact if you have a stanza like above that matches your drive.

Then you typically just call stinit with no args.

Greg

The OP is asking about the density code for the drive -not- compression setting. I think the density setting has something to do with the amount of data that will fit on a tape (haven't found info yet). On my DDS-3 it is set to 0x25 (unknown) according to the status command.

What do you tell your DAT drive when you stick a DDS-2 tape in it?? I don't tell mine anything and it reads it as a DDS-2. Same thing would happen for writing. DAT drives are smart and don't need to be told what type of tape (DDS-2, 3, 4 etc) you've put in it. At least that's what happens on drives worth their salt.

2005/8/11, Ken Schneider :

On Thu, 2005-08-11 at 19:32 -0400, Greg Freemyer wrote:

...

On 8/11/05, Sebastian Jeremias wrote:

...

I didn't try that because I don't know the density value to pass to stinit. Do you know it?

A quick google comes up with:

# My guess for DDS-4 manufacturer=SONY model = "SDT-10000" { scsi2logical=1 can-bsr can-partitions auto-lock mode1 blocksize=0 compression=1 mode2 blocksize=1024 compression=1 mode3 blocksize=0 compression=0 mode4 blocksize = 1024 compression=0 }

That is the entry that goes into /etc/stinit.def

Mode1 is the default I think. blocksize=0 means it is variable. compression=1 enables compression. (I think more precise densities can be set here also, but make sure you have compression working first.)

If you look at your dmesg output after a boot, you should be able to verify the above manufacturer and model match your drive. the above will only have an impact if you have a stanza like above that matches your drive.

Then you typically just call stinit with no args.

Greg

The OP is asking about the density code for the drive -not- compression setting. I think the density setting has something to do with the amount of data that will fit on a tape (haven't found info yet). On my DDS-3 it is set to 0x25 (unknown) according to the status command.

-- Ken Schneider UNIX since 1989, linux since 1994, SuSE since 1998

"The day Microsoft makes something that doesn't suck is probably the day they start making vacuum cleaners." -Ernst Jan Plugge

-- Check the headers for your unsubscription address For additional commands send e-mail to suse-linux-e-help@suse.com Also check the archives at http://lists.suse.com Please read the FAQs: suse-linux-e-faq@suse.com

By the way, i think it's better to use "mtst" instead of "mt" CI.-

From: "Ken Schneider"

Just did a mtst -f /dev/st0 densities and the correct setting for DDS-4 should be 0x26. The OP I believe had a code of 0x8c EXB-8505 compressed. Perhaps that is why he is having problems fitting all of his data on a single tape.

Yes, that's exactly the problem... Yesterday I connected another DAT, that was in another Solaris box. Under Solaris I do a mt status and it says DDS-4. Under Suse, it says EXB-8505, just like the other DAT. I already tryied to use 0x26 density, but it seems to have no effect, because I do a status again and I keep seeing EXB-8505. What I was asking for was the DDS-4 density in bpi, so I can pass it to dump as a command line parameter. Also tryied with stinit, but didn't work. I could change between "default" (0x0) and EXB-8505 (0x8c) densities, and between compression on and off, but no DDS-4 at all. Anyway, I'm already working on a three-levels dump backup schedule :( I'm starting to give up with this... It could be the kernel scsi drivers or the scsi controller (but I don't think so). I already downloaded new "drivers" from HP, but I don't think they are actually "drivers". It's more like a diagnostic application, that didn't help at all... Thanks to all BTW: Ciro, I prefer mtst too :)

On Thursday 11 August 2005 10:28 pm, Ken Schneider wrote:

The OP is asking about the density code for the drive -not- compression setting. I think the density setting has something to do with the amount of data that will fit on a tape (haven't found info yet). On my DDS-3 it is set to 0x25 (unknown) according to the status command.

--

I don't believe I have ever seen the OP mentioned what type of tape he is using. Is it really DDS-4 tape media?? Or what? -- +----------------------------------------------------------------------------+ + Bruce S. Marshall bmarsh@bmarsh.com Bellaire, MI 08/11/05 22:50 + +----------------------------------------------------------------------------+ "If a cow laughed, would milk come out her nose?

Ken Schneider wrote:

Try this command instead:

mt -f /dev/st0 datcompression

to see the status of compression. Use mt -f /dev/st0 datcompression 2 to turn it on.

I've already checked that out: twist:~ # mt -f /dev/st0 datcompression Compression on. twist:~ # That's why I think what's wrong is the density it's using, since it's EXB-8505 and should be DDS-4.