software vs hardware compression with large backups to LTO7

now had a bit of time running with LTO7, Amanda 3.4.5, and letting the tape drive do hardware compression. It happens that I (and some others on the list) couldn't figure out how to turn off compression on the LTO7, but I was already motivated to try running with hardware compression. I'm now

Re: Software vs: Hardware compression

I could. But, I already have on the order of 150 DLEs spread across several servers for each Amanda server. Amanda's inherent multi-threading allows for multiple dumpers per server being backed up, restricted by spindle number. So, typically, when Amanda fires off, I might have 6 or 8 dump

Re: Software vs: Hardware compression

On Friday 28 October 2016 14:27:22 Charles Curley wrote: > On Fri, 28 Oct 2016 15:44:09 -0400 > > Chris Hoogendyk wrote: > > If it were "only" the Amanda server, I could go all out with pigz. > > However, it is also the department server and runs mail, web, samba, > >

Re: Software vs: Hardware compression

On Fri, 28 Oct 2016 15:44:09 -0400 Chris Hoogendyk wrote: > If it were "only" the Amanda server, I could go all out with pigz. > However, it is also the department server and runs mail, web, samba, > printing, etc. If I were to top out all the cores with pigz, I would >

Re: Software vs: Hardware compression

If it were "only" the Amanda server, I could go all out with pigz. However, it is also the department server and runs mail, web, samba, printing, etc. If I were to top out all the cores with pigz, I would have everyone in the department complaining about performance on other services. On

Re: Software vs: Hardware compression

On 10/28/2016 02:37 PM, Chris Hoogendyk wrote: > all of the data is being compressed, and the compression is significant, > but it has become the bottleneck. Top shows multiple of Amanda's gz > processes at the top of the list all day. In your setup, are there enough DLEs to compress that Amanda

Re: Software vs: Hardware compression

On 10/28/2016 02:37 PM, Chris Hoogendyk wrote: > It also knows what a particular DLE can be compressed to based > on the history. If the tape drive is doing the compression, then it is a > black box. Amanda doesn't know what the DLE got compressed to, and it > doesn't know how that relates to the

Re: Software vs: Hardware compression

in hardware compression of the tape drive itself? Is that in fact still the current recommendation? -Sandro -- --- Chris Hoogendyk - O__ Systems Administrator c/ /'_ --- Biology & Geosciences Departments (*) \(*) -- 315 Morrill Science Ce

Software vs: Hardware compression

Why does Amanda recommend the use of software compression vs: the built in hardware compression of the tape drive itself? Is that in fact still the current recommendation? -Sandro

Re: Hardware Compression

{ comment just produced by tapetype prog (hardware compression off) length 386048 mbytes filemark 0 kbytes speed 65651 kps } define tapetype LTO3_320 { comment just produced by tapetype prog (hardware compression off) length 386048 mbytes

Re: Hardware Compression

On 2007-08-14 04:18, Ralf Auer wrote: Hello everybody, if you don't mind, I have two questions concerning hardware compression. I have two HP Ultrium 960 drives. Up to now I used them with hardware compression disabled and compressed my data on the clients. Now I enabled hardware

Re: Hardware Compression

Auer wrote: Hello everybody, if you don't mind, I have two questions concerning hardware compression. I have two HP Ultrium 960 drives. Up to now I used them with hardware compression disabled and compressed my data on the clients. Now I enabled hardware compression and ran amtapetype

Hardware Compression

Hello everybody, if you don't mind, I have two questions concerning hardware compression. I have two HP Ultrium 960 drives. Up to now I used them with hardware compression disabled and compressed my data on the clients. Now I enabled hardware compression and ran amtapetype. 1

Re: Hardware Compression

On Tue, Aug 14, 2007 at 04:18:51AM +0200, Ralf Auer wrote: Hello everybody, if you don't mind, I have two questions concerning hardware compression. I have two HP Ultrium 960 drives. Up to now I used them with hardware compression disabled and compressed my data on the clients

Re: Hardware Compression

Hi Jon, LTO is unusual. When hwc is enabled each input block is compared with and without compression. The smaller of the two is recorded. As amtapetype feeds random data, data that is not compressible, the original input block is taped. Thus you see the same results with or without hwc

software compression vs hardware compression

Hi all, I just wanted to share my experience. I'm usually using hardware compression on my backup server (because all data to be backuped ,1.2TB, are local) to save it some CPU. As a result my backup were going quite fast (about 4 hours) but the load balancing was far from my expectation

Re: Hardware compression and dump size problems

Chris Cameron wrote: I have a DLT-8000. 40/80 Gig tapes. I want to backup a 50 gig partition and am going to use hardware compression. Amanda says the dump won't fit. This configuration was working with server compression turned on and a different tape drive. Error: NOTES: planner

Re: Hardware compression and dump size problems

Toomas Aas wrote: BTW, I'm using a DLT1 drive (40 GB native) with hardware compression. My typical backup run is ca 40 GB, but after the new year, when Amanda autoflushed all the christmas-time dumps from the holding disk, it hit EOT at approximately 52 GB. Your data is different from mine

Hardware compression and dump size problems

This seems like it'd be a common occurrence but I've looked all over. I have a DLT-8000. 40/80 Gig tapes. I want to backup a 50 gig partition and am going to use hardware compression. Amanda says the dump won't fit. This configuration was working with server compression turned

Re: Hardware compression and dump size problems

. Brian On Wed, Jan 03, 2007 at 12:01:50PM -0700, Chris Cameron wrote: This seems like it'd be a common occurrence but I've looked all over. I have a DLT-8000. 40/80 Gig tapes. I want to backup a 50 gig partition and am going to use hardware compression. Amanda says

Re: Hardware compression and dump size problems

On Wed, 3 Jan 2007 at 12:01pm, Chris Cameron wrote I have a DLT-8000. 40/80 Gig tapes. I want to backup a 50 gig partition and am going to use hardware compression. Amanda says the dump won't fit. *snip* What do I need to do to have AMANDA try writing this all to tape? I realize it can't know

Re: Disabling LTO-2 hardware compression

Gordon J. Mills III [EMAIL PROTECTED] writes: Sven, if you don't mind my asking...how did you setup stinit? I installed it but it seems a bit confusing as to what I need to do to have it disable compression on reboots, etc. Read the stinit manpage, make an entry for your tape drive in

RE: Disabling LTO-2 hardware compression

, 2006 10:02 AM To: Graeme Humphries Cc: [EMAIL PROTECTED]; 'amanda users list' Subject: Re: Disabling LTO-2 hardware compression Graeme Humphries [EMAIL PROTECTED] writes: Gordon J. Mills III wrote: Just a note on this: There needs to be a tape in the drive when you execute

RE: Disabling LTO-2 hardware compression

Of Michael Loftis Sent: Tuesday, May 02, 2006 2:21 PM To: Guy Dallaire; amanda users list Subject: Re: Disabling LTO-2 hardware compression mt -f st device datcompression 0 That should work but it will likely come back on after a restart though. --On May 2, 2006 10:17:48 AM -0400 Guy

Re: Disabling LTO-2 hardware compression

Gordon J. Mills III wrote: Just a note on this: There needs to be a tape in the drive when you execute that command...at least on my drives. Anyone have any further info on this? We've seen the same thing, the command fails if there's tapes in the changer but not in the drive on our

RE: Disabling LTO-2 hardware compression

are AIT35 autoloaders. Regards, Gordon -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Loftis Sent: Tuesday, May 02, 2006 2:21 PM To: Guy Dallaire; amanda users list Subject: Re: Disabling LTO-2 hardware compression mt -f st device

Re: Disabling LTO-2 hardware compression

is, the tape drive in the library always seems to have hardware compression ON. There is no way on the library operator panel to force the compression OFF. How did you find out? Used amtapetype -c? (just curious) I've heard that LTO2 drives can easily cope with already compressed data (and do

RE: Disabling LTO-2 hardware compression

has some power struggle with Tandberg SLR7 and LTO-1 hardware compression. I lost. Seriously, I tried to switch hw comp. off with Linux scsi commands (see older threads SLR7 in this list) and at the end I had to send the drive to Tandberg for repair. Until now I don't know what happened exactly

Re: Disabling LTO-2 hardware compression

already. Problem is, the tape drive in the library always seems to have hardware compression ON. There is no way on the library operator panel to force the compression OFF. ... Has anyone devised a way to force hw compression off on a similar setup ? Fedora, and I presume centos, has

Re: Disabling LTO-2 hardware compression

Ultrium tape drive. My tape server is a centos 4.2 box (RHEL 4 clone) I'm using software compression with amanda 2.4.5p1 already. Problem is, the tape drive in the library always seems to have hardware compression ON. There is no way on the library operator panel to force the compression OFF. I've

Re: turn off hardware compression

, it shows that the tape is out of space. I suspect something wrong with the hardware compression. Is there a command to check if the hardware compression is on or off? how can I turn it on or off? Thanks in advance

turn off hardware compression

, it shows that the tape is out of space. I suspect something wrong with the hardware compression. Is there a command to check if the hardware compression is on or off? how can I turn it on or off? Thanks in advance

Re: Disabling hardware compression

On Sat, 30 Oct 2004 22:00:30 -0500, Erik Anderson [EMAIL PROTECTED] wrote: Thanks for the tips, Gene. Between this information, and the info Paul pointed me to, I should be all set. Just an update about this...I determined that the compression can be turned off through the menu of the tape

Re: Disabling hardware compression

Erik Anderson wrote: Hello - I have a Quantum DLT7000 drive, and I'm wondering how I go about disabling hardware compression on it. I did some searching, and it seems that I should be able to issue this command: lpdlnx00 LPD # mt -f /dev/nst0 compression 0 /dev/nst0: Input/output error I don't

Re: Disabling hardware compression

On Sat, 30 Oct 2004 13:12:25 +0200, Paul Bijnens [EMAIL PROTECTED] wrote: Search Google for: squared kosher amanda compression Thanks Paul! I haven't had the time to read through those threads yet, but will do so soon! -Erik

Re: Disabling hardware compression

On Sat, 30 Oct 2004 01:27:53 -0400, Gene Heskett [EMAIL PROTECTED] wrote: To defeat that, and make an uncompressed tape out of a tape that has been written with the compression on, will require that the correct software command be issued (in my case it wasn't a 0, but an 'off' command issued

Disabling hardware compression

Hello - I have a Quantum DLT7000 drive, and I'm wondering how I go about disabling hardware compression on it. I did some searching, and it seems that I should be able to issue this command: lpdlnx00 LPD # mt -f /dev/nst0 compression 0 /dev/nst0: Input/output error I am certain that /dev/nst0

Re: Disabling hardware compression

On Friday 29 October 2004 23:23, Erik Anderson wrote: Hello - I have a Quantum DLT7000 drive, and I'm wondering how I go about disabling hardware compression on it. I did some searching, and it seems that I should be able to issue this command: lpdlnx00 LPD # mt -f /dev/nst0 compression 0 /dev

Re: enabling hardware compression ?

In a message dated: Mon, 23 Aug 2004 15:12:52 EDT Frederic Medery said: Thanks, in fact what I want is to speed up my backup so i moved my tape charger to the biggest server, now I have a /amanda with 160 GB of free space. I thought that HW compression would also speed up my backup. I find

Re: enabling hardware compression ?

On Friday 03 September 2004 11:06, [EMAIL PROTECTED] wrote: In a message dated: Mon, 23 Aug 2004 15:12:52 EDT Frederic Medery said: Thanks, in fact what I want is to speed up my backup so i moved my tape charger to the biggest server, now I have a /amanda with 160 GB of free space. I thought

Re: enabling hardware compression ?

, Aug 23, 2004 at 02:52:29PM -0400, Frederic Medery wrote: Hello, I'm using amanda with IBM 3581 tapechanger, my tapetypes.conf is : # IBM LTO Ultrium 3581 tape Charger define tapetype IBM-LTO3581 { comment IBM LTO Ultrium 3581 (Hardware Compression off) length 100608 mbytes

Re: enabling hardware compression ?

On Mon, 23 Aug 2004 at 3:33pm, Brian Cuttler wrote You might even find its worthwhile to compress some partitions on clients and some on the server, depending on where your free CPU time is and where/if you have any network bottlenecks. Each DLE can be individually selected for

howto disable hardware compression on redhat linux

Hi all, Howto disable hardware compression on redhat linux? In the Unix Backup Recovery book, the author says that this is done mostly by using a specific device name. Which is this device for a redhat linux? Thank you, Bruno Negrão

RE: howto disable hardware compression on redhat linux

, September 22, 2003 2:05 PM To: amanda users Subject: howto disable hardware compression on redhat linux Hi all, Howto disable hardware compression on redhat linux? In the Unix Backup Recovery book, the author says that this is done mostly by using a specific device name. Which is this device

RE: howto disable hardware compression on redhat linux

On Mon, 22 Sep 2003 at 2:30pm, Martinez, Michael wrote The devices /dev/*st0 Various letters in front of st0 mean different things, like no-rewind, no-compress, etc. I've always used 'mt -f /dev/nst0 compression 0' for AIT style tapes and the appropriate density code for Exabyte style

Re: howto disable hardware compression on redhat linux

* Bruno Negrão [EMAIL PROTECTED] [20030922 14:36]: Hi Martinez, The devices /dev/*st0 Various letters in front of st0 mean different things, like no-rewind, no-compress, etc. I already knew that. But I´m asking for what is the exact letter for disabling hardware compression

RE: howto disable hardware compression on redhat linux

Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Bruno Negrão Sent: Monday, September 22, 2003 12:37 PM To: Martinez, Michael; amanda users Subject: Re: howto disable hardware compression on redhat linux Hi Martinez, The devices /dev/*st0 Various letters in front

Re: howto disable hardware compression on redhat linux SOLVED

extract_list - child returned non-zero status: 2 Now its fixed. Thanks, Bruno Negrao. - Original Message - From: Amanda Admin [EMAIL PROTECTED] To: amanda users [EMAIL PROTECTED] Sent: Monday, September 22, 2003 3:52 PM Subject: RE: howto disable hardware compression on redhat linux Bruno

Hardware Compression

I have a couple of Seagate Ultrium 100/200GB tape drives in a Sun/Quantum ATL L25 tape library. When I try to run hardware compression (/dev/rmt/0hbn) on them I still can only fit 100GB of data according to Amanda. I ran amtapetype and got the following: define tapetype ATL-LTO1

Re: Hardware Compression

On Mon, Aug 04, 2003 at 10:28:29AM -0500, Bob Zahn wrote: I have a couple of Seagate Ultrium 100/200GB tape drives in a Sun/Quantum ATL L25 tape library. When I try to run hardware compression (/dev/rmt/0hbn) on them I still can only fit 100GB of data according to Amanda. I ran amtapetype

Re: Hardware Compression

On Monday 04 August 2003 11:28, Bob Zahn wrote: I have a couple of Seagate Ultrium 100/200GB tape drives in a Sun/Quantum ATL L25 tape library. When I try to run hardware compression (/dev/rmt/0hbn) on them I still can only fit 100GB of data according to Amanda. I ran amtapetype and got

RE: DAT DDS4 size or avoiding hardware compression on Linux/Debian

The HP DAT40 drives have dip switches to turn off hardware compression. If you have one of the external drives you need to open the case in order to get to the dip switches at the bottom of the drive... You can find the description in the manual or online from http://www.hp.com/products1/storage

Re: DAT DDS4 size or avoiding hardware compression on Linux/Debian

On Monday 25 November 2002 11:56, Ronan KERYELL wrote: I'm in trouble with a HP SureStore DAT40 (DDS-4) since I cannot write compressed partition past 16GB instead of achieving the theoretical 20GB. I guess it is because the drive is in hardware compression mode, but I do not know how

turn off hardware compression

We are using Compaq 15/30GB DLT's (DLT2000) and I have a question regarding hardware compression. Judging from this group and the Amanda docs one should turn hw compression off. My problem is while this can be done from the front panel of the units the setting does not stick so I have to do

RE: turn off hardware compression

take the correct tape device, usually /dev/nrmt0l on Compaq/T64. This device does no compression, while the others (/dev/nrmt0[hc..]) use more or less of hardware compression. |= We are using Compaq 15/30GB DLT's (DLT2000) and I have a |= question regarding |= hardware compression. Judging

Re: turn off hardware compression

On Fri, Oct 04, 2002 at 02:08:07PM +0200, Per olof Ljungmark wrote: take the correct tape device, usually /dev/nrmt0l on Compaq/T64. This device does no compression, while the others (/dev/nrmt0[hc..]) use more or less of hardware compression. Are there any knowledgeable people around

Re: turn off hardware compression

On Friday 04 October 2002 05:33, Per olof Ljungmark wrote: We are using Compaq 15/30GB DLT's (DLT2000) and I have a question regarding hardware compression. Judging from this group and the Amanda docs one should turn hw compression off. My problem is while this can be done from the front panel

Re: turn off hardware compression

At 10:15 10/4/2002 -0400, Gene Heskett wrote: On Friday 04 October 2002 05:33, Per olof Ljungmark wrote: We are using Compaq 15/30GB DLT's (DLT2000) and I have a question regarding hardware compression. Judging from this group and the Amanda docs one should turn hw compression off. My

hardware compression...

OK I know that's a bad thing to say around here BUT... I'm backing up some Solaris 2.6 machines and need to be able to do a restore with nothing but the O/S CD-ROM. Since it doesn't have gzip or any other compression software on the ROM I am just doing straight ufsdumps (level 0 every night) to

Re: hardware compression...

On Tue, 13 Aug 2002 at 1:38pm, Scott Sanders wrote OK I know that's a bad thing to say around here BUT... No, not really. ufsdumps (level 0 every night) to tape using amanda. My question is, since the drive is handling the compression what tape length should I be specifying in my tapetype

Re: hardware compression...

Here is a typical amanda report using software compression so do you think 40% is safe? HOSTNAME DISKL ORIG-KB OUT-KB COMP% MMM:SS KB/s MMM:SS KB/s -- - hacksaw / 0 1146303 454464 39.6 8:40

Re: hardware compression...

On Tue, 13 Aug 2002 at 1:55pm, Scott Sanders wrote Here is a typical amanda report using software compression so do you think 40% is safe? It's as good a guess as any. You'll know you're being too optimistic if you hit EOT. :) -- Joshua Baker-LePain Department of Biomedical Engineering

Re: hardware compression...

recently, I was running a DLT-7000, HW compression, Solaris 2.6, and I used: define tapetype DLT-7000HC { comment DLTtape IV half-inch cartridge for DLT-7000, hardware compression # assume compression ratio 0.58, length = 35000/.58 mbytes length 60344 mbytes filemark 8 kbytes

Re: Tapetype when utilizing hardware compression

, not smaller. What it boils down to is that the values you get from tapetype will be truely the absolute worst case values. Typical hardware compression will gain 2/1 on text and such sparse files, while a really good software algorythm can easily double that again. However, the hardware

Question about tape drives and hardware compression...

Hi! I have a Seagate DDS-3 drive, attached to a FreeBSD 4.5-release computer. When ever the system restarts, it by default turns on hardware compression. As I wish to use software compression, this could present a problem. I tried writing a shell script that would run at startup which

Re: Question about tape drives and hardware compression...

On Fri, 29 Mar 2002 at 3:27pm, Morse, Richard E. wrote So, in order to work around this, I have modified amdump, and put at the _very_ start, the 'mt -f /dev/nrsa0 comp off' line. This is, however, rather a hack. I would much rather be able to do this at startup, as it should be done.

RE: Question about tape drives and hardware compression...

and hardware compression... Hi! I have a Seagate DDS-3 drive, attached to a FreeBSD 4.5-release computer. When ever the system restarts, it by default turns on hardware compression. As I wish to use software compression, this could present a problem. I tried writing a shell script that would run

Re: Hardware compression (HP DAT 40i users?)

it myself! ii) Thanks Joshua John (Jackson) for the tips on the tapelength when using hardware compression. I'll try to lie to amanda :( for a few runs and see what I get for every fs. iii) After thinking a bit on what Gene wrote regarding hardware compression (Generally speaking, the hardware

Re: Hardware compression (HP DAT 40i users?)

think he was talking about tar vs. dump. I think he was pointing out that if your data is already compressed, sending it a tape drive that was set up to do hardware compression is not going to work well. Compressing compressed data a second time usually ends up expanding it. I use hardware

Re: Hardware compression (HP DAT 40i users?)

HW compression ON host control ON and I can manage it myself! ii) Thanks Joshua John (Jackson) for the tips on the tapelength when using hardware compression. I'll try to lie to amanda :( for a few runs and see what I get for every fs. iii) After thinking a bit on what Gene wrote regarding

Re: Hardware compression (HP DAT 40i users?)

I've read elsewhere. Not trying to speak for Gene, but I don't think he was talking about tar vs. dump. I think he was pointing out that if your data is already compressed, sending it a tape drive that was set up to do hardware compression is not going to work well. Compressing compressed data

Hardware compression (HP DAT 40i users?)

I'm trying to understand why amanda is only writing approximately 19-20 GB on my DDS-4 tapes (HP C5718A, min 20GB and up to 40GB with compression). Supposedly, my DAT40i drive is set from factory with hardware compression ON, and host control ON. According to the documentation that came

Re: Hardware compression (HP DAT 40i users?)

to understand why amanda is only writing approximately 19-20 GB on my DDS-4 tapes (HP C5718A, min 20GB and up to 40GB with compression). Supposedly, my DAT40i drive is set from factory with hardware compression ON, and host control ON. According to the documentation that came with the driver

Re: Hardware compression (HP DAT 40i users?)

-DAT40 { comment just produced by tapetype program length 19560 mbytes filemark 1147 kbytes speed 2957 kps lbl-templ /usr/local/etc/amanda/normal/HP-DAT.ps } That's part of your problem. To use hardware compression, you need to lie to amanda about your tapelength. How much

Re: Hardware compression (HP DAT 40i users?)

On Tuesday 26 March 2002 05:53 pm, Fernan Aguero wrote: I'm trying to understand why amanda is only writing approximately 19-20 GB on my DDS-4 tapes (HP C5718A, min 20GB and up to 40GB with compression). Supposedly, my DAT40i drive is set from factory with hardware compression ON, and host

Re: Hardware compression (HP DAT 40i users?)

it as an upper bound. In general, it's not a good idea to lie to Amanda :-). However, in the case of hardware compression (which I use because software compression would push my backup time to well over 24 hours), you have to trick it with a guess at what will actually fit. One way to do that is to set

Tapetype when utilizing hardware compression

I ran the tapetype test to our tapedrive (ADIC DS9400D) using DLTTAPE IV. I frontpaneled the compression so I expected at least 40 GB when the tapetype was completed. But I only got about 17GB: Command: tapetype -d /dev/rmt/0ndefine tapetype unknown-tapetype { comment "just produced by

Re: Tapetype when utilizing hardware compression

on the front panel. It's still hardware compression. Both ways I would of expected close to double the native writes. Any ideas why the compression would not of increased. Well, double is *always* optimistic. But, as I said above, random data doesn't compress. To use amanda with hardware

RE: Tapetype when utilizing hardware compression

If you read the instructions for tapetype, it says to run it without compression. It will typically report close to your native capacity which it looks like it is doing. -Original Message-From: Don Potter [mailto:[EMAIL PROTECTED]]Sent: Thursday, January 17, 2002 8:11 AMTo:

Re: Tapetype when utilizing hardware compression

IIRC, the tapetype test uses random data, so hardware compress may (?) actually increase the amount of the data. -Kevin Zembower - E. Kevin Zembower Unix Administrator Johns Hopkins University/Center for Communications Programs 111 Market Place, Suite 310 Baltimore, MD 21202 410-659-6139

Re: Tapetype when utilizing hardware compression

, not smaller. What it boils down to is that the values you get from tapetype will be truely the absolute worst case values. Typical hardware compression will gain 2/1 on text and such sparse files, while a really good software algorythm can easily double that again. However, the hardware

Re: Tapetype when utilizing hardware compression

. Typical hardware compression will gain 2/1 on text and such sparse files, while a really good software algorythm can easily double that again. However, the hardware compression can be easily defeated by preceeding it with a good software compressor so that the copy on the tape might be 10

Hardware Compression Problem

We are currently using a StoreEdge L280 Multichanger tape unit to backup via Amanda v2.4.1p1. When switching on hardware compression on the tape unit, Amanda seems to override this setting switching hardware compression off. Can anyone tell me how to make the tape units hardware

Re: Hardware Compression Problem

We are currently using a StoreEdge L280 Multichanger tape unit to backup via Amanda v2.4.1p1. What OS on your tape server? When switching on hardware compression on the tape unit, Amanda seems to override this setting switching hardware compression off. Amanda does not do that kind of thing

Hardware Compression and tape capacity

Hello Folks, Many thanks to John R. Jackson and Yura Pismerov for their answers concerning estimating the tape size by hand for hardware compression. Regards... -- Luc Lalonde, Responsable du reseau GIREF Telephone: (418) 656-2131 poste 6623 Courriel: [EMAIL PROTECTED] begin:vcard

Re: Tapetype: Hardware compression

ce a month. I just have one problem in that I don't think that the "tapetype" program calculated the capacity of my tapes with hardware compression. Here's the result that I got (I posted it on the FAQ-O-MATIC): define tapetype Maxell-DDS4-Hardware-Compress { comment "M

Re: Tapetype: Hardware compression

However, I'd like to create a "Monthly" profile to complement my "Daily" profile to do full backups of everything once a month. OK. I just have one problem in that I don't think that the "tapetype" program calculated the capacity of my tapes with hardware compr

Re: Linux, AIT2 and hardware compression

On Fri, 9 Feb 2001 at 10:36pm, Mitch Collinsworth wrote mt status says the same thing no matter what I do with mt comp, mt compression, mt setdensity, etc. And now I've tried with mt 0.6, too. Strange. That's right, there's no indication in the 'mt stat' line whether hardware compression

Re: Linux, AIT2 and hardware compression

On Thu, 8 Feb 2001, Yura Pismerov wrote: mt comp off should work fine for AIT2. At least is working for me. How do you know it does not work ? I don't. It should be reported by "mt status". mt status says the same thing no matter what I do with mt comp, mt

Linux, AIT2 and hardware compression [was: FreeBSD, DLT 2000 andhardware compression ...]

On Tue, 6 Feb 2001, Dan Wilder wrote: On Tue, Feb 06, 2001 at 10:36:19PM -0500, Mitch Collinsworth wrote: Sorry, I haven't messed with this myself. I'm currently staring at the Linux docs trying to figure out if I have to use ioctl in order to turn h/w compression on and off there.

Re: FreeBSD, DLT 2000 and hardware compression ...

I have a DLT2000 (is that 5/10 or 15/30?) ... If I'm reading the www.quantum.com web page right, it's 10/20 if you use DLT-III tapes and 15/30 if you use DLT-III-XT. will it automatically use hardware compression under FreeBSD, or, like Solaris, do I have to use special devices

Re: FreeBSD, DLT 2000 and hardware compression ...

which man page are you reading here? :) www.freebsd.org John R. Jackson, Technical Software Specialist, [EMAIL PROTECTED]

Re: FreeBSD, DLT 2000 and hardware compression ...

On Tue, 6 Feb 2001, John R. Jackson wrote: which man page are you reading here? :) www.freebsd.org I think he meant man page for which command. (You overlooked saying in your last message.) I imagine you're looking at mt(1) which contains: comp Set compression mode. There are

Re: FreeBSD, DLT 2000 and hardware compression ...

On Tue, Feb 06, 2001 at 10:36:19PM -0500, Mitch Collinsworth wrote: Sorry, I haven't messed with this myself. I'm currently staring at the Linux docs trying to figure out if I have to use ioctl in order to turn h/w compression on and off there. Should be able to do it with mt(1). At least,

Re: hardware compression and amanda

"Olaf Seidel" [EMAIL PROTECTED] writes: Hi, how do I use hardware compression of the tape drive? I used "compress none" in amanda.conf and set up compression for the tape with "mt -f /dev/nst0 compression on". But the Amanda mail report announced, that

Re: hardware compression and amanda

If you set a tape type without hardware compression Amanda AFIK does not use the space gained by compression. ... Only partially true. As I said, when you use hardware compression you have to lie to Amanda about the tape length, inflating the value by the amount you expect to be able to get

Re: hardware compression and amanda

[ Apologies if this appears twice. The first try bounced. --JJ ] how do I use hardware compression of the tape drive? I used "compress none" in amanda.conf and set up compression for the tape with "mt -f /dev/nst0 compression on". But the Amanda ma