Hi Gene
I am using DDS-4 DAT tapes 20GM native and 40GB compression So I hope
amanda using
and amanda, using gzip, can probably put well over 40GB on the tape if
your are correct.
Cheers
On Fri, 2005-09-30 at 11:33 -0400, Gene Heskett wrote:
> On Friday 30 September 2005 08:09, Chuck Amadi Systems Administrator
> wrote:
> >Hi all and Scott
> >
> >I am trying a Monthly archive but in order to follow a setup similar to
> >Scott I need a tape changer.
> >
> >I have found a SCSI tape drive spec below it was once used for backups
> >prior to moving over to Amanda.
> >
> >External Seagate DAT subsystem for NT, Windows, NetWare, DDS-3
> >recording format, consists of STD124000N DAT drive (data
> >transfer rate 2.2 MB/s, 24 GB capacity with DDS-DC data
> >compression), tabletop enclosure, tape, 1 m cable with 50pin
> >high density plug,
> >
> >Thus could this possible be used a a tape changer I have checked the
> >Amanda homepage but doesn't mention any devices.
> >
> >Cheers
> >
> >Chuck
>
> It should work just fine, Chuck, as long as thats a large enough
> tape. With hardware compression off, it will hold 12GB, and amanda, using
> gzip, can probably put well over 24GB on the tape.
>
> The only caveat is the tape format. Its cheap, and in DDS2's at
> least, I had tape trouble after 20-50 passes per tape. They claim a
> million passes, but the drives heads are worn out long before that in
> my experience. Rotary heads, are like your vcr in design, and the
> lifetime is measured in a small number of thousands of hours, like
> 3 to 5 for the life of the head. I've had maybe 1% of the problems I
> had with DDS2 tapes since I switched to the FILE device on a 200GB drive.
>
> For rotating heads, the head wear and damage occurs as each head tip
> engages the edge of the tape at the start of the track, there is tape
> contact and bounce there, but once 'on' the tape, there is a micron
> thick air cushion between the tape and the head tip. Its that crash
> at the entrance edge of the tape that does the damage. I've looked
> at tips that were actually shattered in my many years of keeping
> broadcast recorders going. DVC-PRO heads are 1/3rd the size of a dat
> head, and they can read and write 100 MB/second these days. But the
> electronics in those is 1000x smarter in terms of error correction
> too. And the error correction doesn't have to be 100%, as long
> as the pixal coming out somewhat resembles what went in, thats good
> enough, the eye is a whole lot more forgiving than data storage.
>
> Todays tape drives are still in the horse and buggy era in comparison.
>
> >On Fri, 2005-09-30 at 07:39 -0400, Scott R. Burns wrote:
> >> Hi Chuck,
> >> Sorry I don't have any experience without a changer. You would be
> >> best to ask the list about this one. There may be a way to have it
> >> pause and prompt for the next tape ?
> >>
> >> I do know that you can pick up the changer I have on Ebay usually for
> >> about $ 100 USD - $ 200 USD with a 30day warrenty. Unfortunately I
> >> bought mine brand new in it's day for about $ 3000 USD :-(
> >>
> >> Scott...
> >>
> >> Scott R. Burns
> >> NETCON Technologies Incorporated
> >> Suite 135 - 4474 Blakie Road
> >> London, Ontario, Canada
> >> N6L 1G7
> >> Voice: +1.519.652.0401
> >> Fax: +1.519.652.9275
> >> Web: www.netcontech.com
> >>
> >> -----Original Message-----
> >> From: Chuck Amadi Systems Administrator [mailto:chuck AT smtl.co DOT uk]
> >> Sent: Friday, September 30, 2005 6:23 AM
> >> To: Scott R. Burns
> >> Subject: RE: My Monthly archive config - issue
> >>
> >>
> >> Hi
> >>
> >> I have received an error after running amcheck Monthly
> >>
> >> WARNING: if a tape changer is not available, runtapes must be set to 1
> >>
> >> Thus I have not got a tape changer
> >>
> >> I just want to amflush data that cannot fit on tape 1 to 2,3 or in the
> >> future tape 4 to backup potential around 80GB.
> >>
> >> Cheers
> >>
> >> Chuck
> >>
> >> On Thu, 2005-09-29 at 12:23 -0400, Scott R. Burns wrote:
> >> > I have a similar setup. I have HW compression turned off on the
> >> > drive (HP DAT24X6 changer).
> >> >
> >> > In my monthly config:
> >> >
> >> >
> >> > dumpcycle 0 weeks
> >> > runspercycle 1
> >> > tapecycle 1000 tapes
> >> > runtapes 3
> >> >
> >> > Also, record is turned off so my normal daily amanda config does not
> >> > think the level 0 has been completed after the monthly.
> >> >
> >> > We never re-use our monthly tapes we send them offsite and leave
> >> > them so thats why I have it set to 1000. We use between 2-3 tapes on
> >> > a monthly run so runtapes is at 3.
> >> >
> >> > Scott...
> >> >
> >> > Scott R. Burns
> >> > NETCON Technologies Incorporated
> >> > Suite 135 - 4474 Blakie Road
> >> > London, Ontario, Canada
> >> > N6L 1G7
> >> > Voice: +1.519.652.0401
> >> > Fax: +1.519.652.9275
> >> > Web: www.netcontech.com
> >> >
> >> > -----Original Message-----
> >> > From: owner-amanda-users AT amanda DOT org
> >> > [mailto:owner-amanda-users AT amanda DOT org]On Behalf Of Chuck Amadi
> >> > Systems Administrator
> >> > Sent: Thursday, September 29, 2005 12:01 PM
> >> > To: Amanda List
> >> > Subject: My Monthly archive config - issue
> >> >
> >> >
> >> > Hi again
> >> >
> >> > Its that time for a monthly archive backup I have currently 80GB
> >> > server and using a DAT DDS-4 20GB native 40GB compression I am aware
> >> > that I cannot have both hardware compression and software
> >> > compression on So Amanda usually behaviour is to have hardware
> >> > compression turned off using the mt command.
> >> >
> >> > Thus my amanda.conf is as follows
> >> >
> >> > I want a full dump for archiving and this tape will pulled out.
> >> > dumpcycle 4 weeks # the number of days in the normal dump
> >> > cycle runspercycle 2 # the number of amdump runs in
> >> > dumpcycle days # (4 weeks * 5 amdump runs per week -- just weekdays)
> >> > tapecycle 12 tapes # the number of tapes in rotation to pull
> >> > each monthly tape for archiving.
> >> >
> >> > runtapes 1 # number of tapes to be used in a normal run.
> >> >
> >> > Should I increase runtapes to 2 to ensure that I backup at a minimum
> >> > 40GB.
> >> > Also should I amend dumpcycle to dumpcycle 0 weeks for a full dump
> >> > and not incremental.
> >> >
> >> > Please advice of the best setup to backup for a monthly archive.
> >> >
> >> > Cheers
> >> >
> >> >
> >> >
> >> >
> >> > --
> >> > Unix/ Linux Systems Administrator
> >> > Chuck Amadi
> >> > The Surgical Material Testing Laboratory (SMTL),
> >> > Princess of Wales Hospital
> >> > Coity Road
> >> > Bridgend,
> >> > United Kingdom, CF31 1RQ.
> >> > Email chuck.smtl.co.uk
> >> > Tel: +44 1656 752820
> >> > Fax: +44 1656 752830
> >>
> >> --
> >> Unix/ Linux Systems Administrator
> >> Chuck Amadi
> >> The Surgical Material Testing Laboratory (SMTL),
> >> Princess of Wales Hospital
> >> Coity Road
> >> Bridgend,
> >> United Kingdom, CF31 1RQ.
> >> Email chuck.smtl.co.uk
> >> Tel: +44 1656 752820
> >> Fax: +44 1656 752830
>
--
Unix/ Linux Systems Administrator
Chuck Amadi
The Surgical Material Testing Laboratory (SMTL),
Princess of Wales Hospital
Coity Road
Bridgend,
United Kingdom, CF31 1RQ.
Email chuck.smtl.co.uk
Tel: +44 1656 752820
Fax: +44 1656 752830
|
