Joshua Baker-LePain ([EMAIL PROTECTED]):
> On Mon, 8 Oct 2001 at 5:36pm, Jeremy Wadsack wrote
>> Lee Fedor ([EMAIL PROTECTED]):
>>
>> >> define tapetype EXB-8505XL {
>> >> comment "Exabyte 8505XL tapes (works with Exabyte 10h changer)"
>> >> length 9584 mbytes
>> >> filemark 917280 kbytes
>> >> speed 667 kps
>> >> }
>> >>
>> >> 1] I'm fairly certain these are 7GB tapes (and even gave -e 7g to
>> >> tapetype when I ran it). Why does tapetype come back saying they are
>> >> 9.5GB?
>>
>> > it getting 9.5 with software compression. which is reasonable.
> Tapetype doesn't use software compression. It just writes random data to
> the drive until it hits EOT.
I guess I knew this. I had assumed that Lee meant 'hardware.'
> This also means that if harware compression
> is enabled, you'll actually see a much *smaller* length than you expect,
> since random data doesn't compress very well. Here's what I got running
> tape type on an Eliant 820 with XL tapes (the Eliant is the same size as
> the 8505XL, just faster):
> define tapetype Eliant-820 {
> comment "just produced by tapetype program"
> length 6680 mbytes
> filemark 0 kbytes
> speed 949 kps
> }
So do you have any idea how tapetype wrote 9.5GB to a 7GB tape?? If
hardware compression would have made it less, then do you think that
there was some kind of tape error?
> Amanda *never* appends, and does rewind the tape when she starts up
> (but not when she's done).
Ok. That behavior makes much more sense.
> Do you mean that in a single night's run, using multiple tapes,
> you're only getting 2GB per tape?
I'm only using one tape per run. But it's only putting 2GB (1GB last
night) on the tapes that had 5GB last week. The change that resulted
in this was the change of tapetype.
> That *could* be a result of combined software/hardware compression,
> but it seems rather extreme. Are there any error messages in the
> system logs?
I am just getting 'dumps way to big, must skip incremental' from
Amanda. As if it thinks the tape is only 2GB, not 7GB. The amanda logs
contain no error messages. The system logs contain nothing related to
the dump.
Does anyone know how to turn off hardware compression on an Exabyte
8505 drive? I can't find any reference to it in the manuals...
Thanks,
--
Jeremy Wadsack
Wadsack-Allen Digital Group
