On Friday 16 January 2004 17:16, Alastair Neil wrote:
>Yes I was aware, I thought using the device file without the "c" in
> it implied no compression. I have searched in vain for information
> about how to turn off compression.
Thats often via a dip-switch setting someplace on the drive. If you
don't have adequate docs on it, you should contact the vendor.
This is not an amanda problem, but we'll try to help you if any of us
has a drive like that one, I do not myself.
If someone on this list has a DLT-8000, please try to help here with
the specifics.
>On Fri, 2004-01-16 at 17:05, donald.ritchey AT exeloncorp DOT com wrote:
>> Alastair:
>>
>> I use the same drive on HP/Compaq Tru64 UNIX.
>>
>> 1. Do NOT use the hardware compression. See the archived for an
>> exhaustive discussion of this topic.
>>
>> 2. Uncompressed capacity of this drive is around 40 GB +/- 2GB.
>>
>> Using a compressed tape device which uncompressible data will
>> actually reduce capacity, since recompressing compressed data
>> makes it expand.
>>
>> Best wishes,
>>
>> Don
>>
>> Donald L. (Don) Ritchey
>> E-mail: Donald.Ritchey AT exeloncorp DOT com
>>
>>
>> -----Original Message-----
>> From: Alastair Neil [mailto:aneil2 AT gmu DOT edu]
>> Sent: Friday, January 16, 2004 2:17 PM
>> To: 'amanda-users AT amanda DOT org'
>> Subject: amtapetype
>>
>>
>> I just ran amtypetype -f /dev/rmt/0bn, a Sun Storedge L9
>> autochanger and recieved the following:
>>
>> define tapetype unknown-tapetype {
>> comment "just produced by tapetype prog (hardware compression
>> on)" length 34169 mbytes
>> filemark 28 kbytes
>> speed 1787 kps
>> }
>>
>> I'm confused because I believed this to be a DLT8000 drive which
>> should be closer to 80 MBytes compressed, and certainly the speed
>> is not what I expected either. I ran amtypetape -c -f /dev/rmt/0bn
>> and amtypetape -c -f /dev/rmt/0cbn and received nearly identical
>> output:
>>
>> amtapetype -c -f /dev/rmt/0cbn
>> Writing 256 Mbyte compresseable data: 27 sec
>> Writing 256 Mbyte uncompresseable data: 56 sec
>> WARNING: Tape drive has hardware compression enabled
>> Estimated time to write 2 * 1024 Mbyte: 448 sec = 0 h 7 min
>> amtapetype -c -f /dev/rmt/0bn
>> Writing 256 Mbyte compresseable data: 25 sec
>> Writing 256 Mbyte uncompresseable data: 56 sec
>> WARNING: Tape drive has hardware compression enabled
>> Estimated time to write 2 * 1024 Mbyte: 448 sec = 0 h 7 min
>>
>> Host is a Sun E250, with HVDS adaptor.
>>
>> Does anyone have experience with this drive?
--
Cheers, Gene
"There are four boxes to be used in defense of liberty: soap,
ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
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Copyright 2004 by Maurice Eugene Heskett, all rights reserved.
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