exabyte dump parameters summary

2007-12-25 7:43:00

Here are the results from my query about dump parameters for an Exabyte 8200.

It is interesting the wide variety of responses (apparently the driver uses

some unknown linear combination of the parameters). I called Exabyte and

they recommended for a 112M tape: 80 54000 6000 and said to use a ratio of

the lengths for the 15M, 54M, etc. They also said that SUNOS has a limit

of 2^31 bytes which is about 2.1G and not 2.3G for a single I/O stream.

Many thanks to all who replied.

                                                Greg

-------------------------------------------------------

  Greg Gilley

  gilley@ndl.COM [Numerical Design Limited]

  919-929-2917 (voice)

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From: Tom Conroy <trc@NSD.3Com.COM>

Hi Greg:

The only parameter that will change will be 's' for size. This has

absolutely no effect on the data written to tape, only on the amount

of tape that dump estimates that it will use and when it thinks it

has run out of tape.

On a Sony P6-120MP (120M), I use 6000 for a size when matched with

the density and blocking in:

        /etc/dump 0udbsf 54000 100 6000 /dev/nrst1 /dev/sd0a

So I would use the following:

        Tape Length Size Parameter

        120 6000

        115 5750

        54 2700

        15 750

Remember, these are only estimates and come with no warranty whatsoever! :^)

Good Luck!

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From: ebumfr@ebu.ericsson.se (Michael Rembis 6259)

This is what I use for my Sony P6-120M tapes:

/usr/etc/dump 0ubdsf 56 54000 6000 machine:/dev/nrst9 /dev/xy0h

Chao !

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From: Eckhard.Rueggeberg@ts.go.dlr.de

We do it with the following script (for 90min tapes) :

if [ $# != 2 ]; then

        echo ""

        echo " Usage : dump_on_exabyte machine_name exatapeserver_name "

        echo ""

        exit 1

fi

if [ `ping $1 | grep -c alive` != 1 ]; then

        echo $1 lebt nicht !!

        exit 1

fi

if [ `ping $1 | grep -c alive` != 1 ]; then

        echo $1 lebt nicht !!

        exit 1

fi

DUMPFILE=dump.tmp.$$

rsh $1 df | grep dev | colrm 10 > $DUMPFILE

for i

in `cat $DUMPFILE`

do

echo ""

echo Dumping $i from $1 on $2

echo ""

rsh $1 /etc/dump 0ucbfs 126 nobody@$2:/dev/nrst9 20000 $i

done

rm $DUMPFILE

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From: kkinners@ios.bc.ca (Kerry Kinnersley)

For the 8200 and the 115M tape I use:

0ucbsdf 126 6000 54000 for level 0 dump.

I don't see why you would want to use the 15M and 54M tapes since they are

so cheap. Don't forget the exabyte summaries are in ftphost.uni-augsburg.de

under /pub, perhaps they are listed in there?

Good Luck!

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From: era@niwot.scd.ucar.EDU (Ed Arnold)

I don't know what you mean by 15M, 54M, and 115M tapes. The usual

dump parms we use with an 8200 writing to a sony P6-120 cartridge are:

dump 0ubdsf 126 54000 6000 /dev/nrst0 /dev/sd2c

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From: ept@eptsun1.ctd.ornl.gov (E P Tinnel)

Hi ...

try

        /etc/dump 0ufbsd /dev/nrst1 100 6000 54000 /dev/rsd0a

for 112m tapes

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From: herman@galileo.csc.ti.com (Herman Schuurman)

Although I have never used dump on our 8200 (we use Networker for

backups), the documentation suggested the following parameters:

        b=50, s=6000, d=54000

I guess you could adapt the size parameter (6000 for a 112m tape), to

account for the smaller 15M and 54M tapes.

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From: ctm@sleepy.boeing.com (chuck malmsten)

We have an bunch of exebyte 8mm drives. I don't know the model

number. Is an 8200 an 8mm drive.

anyway, we use 8mm P120 tapes which hold about 1.3 gigabytes. The only "strange" thing

we do to get dump to write lots of data to these tapes is to tell dump the

tape density is 54000 bytes per inch. We then specify the tape length

accordingly (e.g. 2000 feet for 1.3 gig).

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From: oran@spg.amdahl.com (Oran Davis)

Hi,

Dump uses the 9 track standard as the reference for tape length and capacity.

1600bpi 9 track is standard. The effective length that the dump must see is as though

it is writing to 9 track.

the size parameter you pass to dump(8):

------------------- 4.1.1 manual ----------------------------

     s size

          Specify the size of the volume being dumped to. When

          the specified size is reached, dump waits for you to

          change the volume. dump interprets the specified size

          as the length in feet for tapes, and cartridges and as

          the number of 1024 byte blocks for diskettes. The fol-

          lowing are defaults:

               tape 2300 feet

               cartridge 425 feet

               diskette 1422 blocks (Corresponds to a 1.44 Mb

                           diskette, with one cylinder reserved

                           for bad block information.)

------------------- 4.1.1 manual ----------------------------

G = 1024*1024 (yes! number of 1M chunks)

ts = 2.3*G or 5*G or less if you have short or partially filled tape.

bf = blocking factor. The calture says 124 is best, <64K.

size = ((512 * bf ) + 1920) * (ts - 2048) / (bf * 10667)

example:

 103400.49 = (512*124+1920)*(2044*1024-2048)/124/10667

 dump 0fbs /dev/nrst0 124 103400 /dev/rsd0g

The variouse tape sizes (ts) and standards (on the NTSC transports we all use):

Minutes NTSC PAL

15 258M 368M

30 516M 753M

60 1.032G 1.484G

90 1.548G 2.226G

120 2.044G (PAL: don't use - too thin and will give errors quickly)

Good luck,

>- Oran

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From: Vlastimil Malinek <vlastimil.malinek@mrc-apu.cam.ac.uk>

Greg,

        After much conversation with sun and other colleagues we use the

following parameters on our switchable 8500 exabytes.

# 2 gig length

#length=5190

# 5 gig length

length=10380

/usr/etc/dump ${level}bcdsuf 112 4100000 ${length}

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