|
Re: Hardware compression and dump size problems
2007-01-04 10:05:43
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: cgydc002 /dev/vg01/lv_data 20070103 0 [dump larger than tape,
53128750 KB, full dump delayed]
taper: tape Wk2Tue kb 2088288 fm 4 [OK]
My tape type:
define tapetype DLT8000-40 {
comment "just produced by tapetype program"
length 37482 mbytes
filemark 2362 kbytes
speed 5482 kps
Amanda doesn't really know anything about hardware compression. If you are
using hardware compression, you need to guesstimate yourself how much of
your data will fit to the tape. In the tapetype above you have specified
length 37482 MB, so Amanda doesn't see any sense in trying to write a
53128750 kB dumpfile to tape. You need to increase the length by the factor
of how much you think your hardware compressor is able to compress your data.
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, of course, but I
do think that being able to tape this 53128750 kB dump with 40 GB tape
drive and hardware compression cannot be taken for granted.
--
Toomas Aas --------------------------------------------------------
|arvutivõrgu peaspetsialist | head specialist on computer networks|
|Tartu Linnakantselei | Tartu City Office |
skype: toomas_aas ----------------------------------- +372 736 1274
|
|
|
