On Wed, 22 Jan 2003 at 3:05pm, hochenaw wrote
> But the backup is to slow, we should have a backup rate of 10.8 GB
> (native)/20.6 (comprimized), but we do not have :-(
GB is not a rate, it's a size. I assume you mean GB/hour?
> In the file tapelist we have following entry (i dont know why):
> -------------------------------------------------
> define tapetype HP-DLT {
> comment "HP SureStore DLT"
> length 80 gbytes # conservative estimate
Err, no, actually that's a very optimistic estimate. Very rarely does
hardware compression get you 2:1 as the manufacturers claim. And, if
you're using software compression, you need to *not* use hardware
compression and thus tell amanda the native capacity.
> filemark 1 byte # should work given above
> speed 30 mbytes # even more, but this isn't used in
> amanda
> }
> -------------------------------------------------
> length in comprimized (80) or uncommprimized (40) modus?
Again, it depends on whether you use software or hardware compression.
> What does filemark mean?
The amount of space the tape drive uses when it writes an EOF sequence.
> speed in mbytes per minutes or ...? Does it have any consequence if i
> insert to much/less speed?
Nope.
> How can i activate software or hardware compression (cant find an
> entry in amanda.conf, just Client or Servers best in dumptypes-file)?
Hardware compression is controlled either via dip switches on the drive
itself or software (e.g., 'mt compression 1' on Linux with some drives).
Software compression is controlled in the dumptype.
> > I have differnt directories to backup, and i want to pack them in
> _one_ big package, so i specify a chunk size of 20GB, but Amanda
> creates for each entry in the disklist one package/file.
Yes, that's how it works. Each disk list entry has to be a separate file.
> A hardware question: If i have many packages to flush out to tape, are
> they written at once so that the tape comes into the streaming mode or
> does the tape have to be stopped and restartet for each package newly?
Amanda does it's best to keep the tape streaming.
> What happens if i delete some files in the holding disk manually?
> Does it have consequences and the database is corrupted?
Amanda will think that those directories got backed up, but you don't have
'em any more.
--
Joshua Baker-LePain
Department of Biomedical Engineering
Duke University
|