[comp.unix.wizards] dump and Exabyte Drives

rogerj@batcomputer.tn.cornell.edu (Roger Jagoda) (07/16/90)

Folks,
 
I have inherited a UNIX system (VAX/ULTRIX) with a SCSI Exabyte (OEM'd 3rd Party as usual) Tape unit. My question regards the parameters for the best "dump"
command use. For example, we're using now:
 
dump <level>usdf 4800 6666 /dev/nrmt1h <f. system>
 
This assumes a density or 4800 and a tape length of 6666 feet which CAN't
be correct. Something is wrong as we can't restore files either..:-( 
 
The tape unit responds with "not a dump tape, I/O error"
 
So, the tapes are SONY 120Ps and the ExaByte manual says the drive is capable
of writing "linear recording density = 43200 bits/inch"
 
Now, isn't this the number we should use instead of 4800 (which sounds more 
like a guess from the old 1600 bpi tape reel days..)?
 
As for feet of tape length, we have asked everyone including the mail
order house where the tapes were bought, NO ONE seesm to know how many
feet of tape come on a 120 tape! The actual model number of the tape is
"P6-120MP" for "Metal Particle". If anyone knows how long these tapes
are can they post an answer? Thanks. Actually, couldn't we just put a
very large number for the lenght (like 100000)? That number is just
so the tape doesn't run off the reel during the dump, right? Well, our
dumps don't take up 2.2G so there's probably no danger of that.
 

Should our dump command be more like:
 
dump <level>udsf 43200 100000 /dev/nrmt1h <f.system> ?
 
Thanks in advance for any pointers or comments!
 
--Roger Jagoda
--Cornell University

-- 
-------------------------------------------------------------------------
Roger Jagoda                          -- My employers don't even like paying
Cornell University                         me, let alone accept responsibility
fqoj@cornella.cit.cornell.edu              for anything I say or do! --

jwc@gilda.Solbourne.COM (Jeff Christy) (07/16/90)

The P6-120 8mm cartridge is 346 feet long, according to my documentation.
Hope this helps.
				Jeff Christy
				Solbourne Computer - MIS
P.S. -
SunOS has a file, /etc/media, which describes various tape attributes.  The
dump qualifier -M specifies that you want to use the information given in this
file for some specific tape type.  Does Ultrix have a similar facility ?

wwtz@ciba-geigy.ch (Wolfgang Wetz) (07/17/90)

In article <1990Jul16.143932.3659@Solbourne.COM> jwc@gilda.Solbourne.COM (Jeff Christy) writes:
>The P6-120 8mm cartridge is 346 feet long, according to my documentation.
>Hope this helps.
>				Jeff Christy
>				Solbourne Computer - MIS
>P.S. -
>SunOS has a file, /etc/media, which describes various tape attributes.  The
>dump qualifier -M specifies that you want to use the information given in this
>file for some specific tape type.  Does Ultrix have a similar facility ?

I tried to locate /etc/media in SunOS 4.0.3 and in SunOS 4.1. Unfortunately
my version seems to miss it. Also TFM did not help. Can you provide some
info on the filelayout? Also the dump command in SunOS does not (officially)
know of the -M option. Are you sure the above note corresponds to SunOS?
--
Wolfgang Wetz, Systems Administrator
   ***  CIBA-GEIGY AG, R-1045.P.24, P.O.Box, CH-4002 Basel, Switzerland  ***
E-mail: cgch!wwtz@relay.EU.net - Phone: +4161 697 54 25 - Fax: +4161 697 32 88

bruce@sonyd1.Broadcast.Sony.COM (Bruce Lilly) (07/18/90)

In article <10543@batcomputer.tn.cornell.edu> rogerj@tcgould.tn.cornell.edu (Roger Jagoda) writes:
>So, the tapes are SONY 120Ps and the ExaByte manual says the drive is capable
>of writing "linear recording density = 43200 bits/inch"
> 
>As for feet of tape length, we have asked everyone including the mail
>order house where the tapes were bought, NO ONE seesm to know how many
>feet of tape come on a 120 tape! The actual model number of the tape is
>"P6-120MP" for "Metal Particle". If anyone knows how long these tapes
>are can they post an answer? Thanks.

Consumer 8mm NTSC video is recorded at 1.43 cm/s at standard play
speed. Therefore a 120 minute tape contains 1.43 * 1.2 * 60
meters of tape. The multiplication and units conversion are left
as an exercise for the reader...

-- 
    Bruce Lilly, Product Manager,        | bruce@sonyd1.Broadcast.Sony.COM
    Digital Television Tape Recording,   | uunet!{sonyusa,vmp}!sonyd1!bruce
    Sony Communications Products Co.,    | lilb@sony.compuserve.com (slow)
    Teaneck, NJ 07666  |  Telephone: 1(201)833-5693   | FAX: 1(201)833-9279

jwc@gilda.Solbourne.COM (Jeff Christy) (07/20/90)

>SunOS has a file, /etc/media, which describes various tape attributes.  The
>dump qualifier -M specifies that you want to use the information given in this
>file for some specific tape type.  Does Ultrix have a similar facility ?

  Oops, my mistake - this is a YAUSE (Yet Another Useful Solbourne Extension).
I should have RTFSunOSM before I jumped in  ;-}

				Jeff Christy
				Solbourne Computer - MIS