On Monday 03 October 2005 11:29, Montagni, Giovanni wrote:
>The thing i can't understand is why the tape created with the new drive
> works perfectly... Or you're saying that the old drive have never
> written tape?
No, what I'm saying is that the tracking interchange, eg where the
tracks are located on the tape, is sufficiently different from the old
one that the new one cannot read the old ones tapes, and very likely
vice versa. Thats why I said to yell at the vendor, that drive is
out of adjustment or the old one is so worn its out of standard,
either scenario is equally possible. If, when the new drive has been
adjusted, it still doesn't allow interchange, then the old one is out
of whack, but since its equally out of whack for both writes and
reads, it will be able to read its own, possibly non-standard tapes.
But the new drive may not be able to read the old drives tapes (and
vice versa)
This is exactly the same scenario as when you are
trying to watch a tape in your vcr, and no amount of adjusting the
tracking will get rid of the noise bars in the picture. The entrance
and exit guides are not matched in location from one machine to the
other, or the guides have grooves cut in them from the edge of the
tape passing by which allows the tape to wobble more than half a
track width, either error will cause this tracking problem. And its
only solveable by the replacement of the guides if worn and the proper
mechanical adjustments to these guides. This of course involves
putting passes on a so called and very expensive (several
hundred dollar) standard tape while watching the signal playback on a
scope that is synchronized to the heads rotation. Dealing in video,
service, I'm familiar and used to that, but I'd suspect the vendors
techs may not be that familiar with it.
>Tomorrow i will try to read amanda label on few tapes written by the old
> drive...
>
>-----Messaggio originale-----
>Da: owner-amanda-users AT amanda DOT org [mailto:owner-amanda-users AT amanda
>DOT org]
> Per conto di Gene Heskett Inviato: lunedì 3 ottobre 2005 17.10
>A: amanda-users AT amanda DOT org
>Oggetto: Re: R: Question about changing Tape Drive
>
>On Monday 03 October 2005 08:03, Montagni, Giovanni wrote:
>>This is the output of dd command:
>>
>>[root@auriga root]# dd if=/dev/nst0 bs=32k count=1
>>0+0 records in
>>0+0 records out
>>
>>I also tried to set blocksize to 0 (mt -t /dev/st0 setblk 0 or mt -t
>>/dev/nst0 setblk 0) but nothing has changed... The tape was on the
>>beginning, as i can see with mt -t /dev/st0 status. This means that the
>>old drive stopped to write anything on tape? but amanda report that the
>>backup was executed correctly. In addiction, old drive can read amanda
>>label.
>
>Contact the vendor, that drive is caca.
>
>>-----Messaggio originale-----
>>Da: Paul Bijnens [mailto:paul.bijnens AT xplanation DOT com]
>>Inviato: venerdì 30 settembre 2005 10.34
>>A: Montagni, Giovanni
>>Cc: amanda-users AT amanda DOT org
>>Oggetto: Re: Question about changing Tape Drive
>>
>>Montagni, Giovanni wrote:
>>> I have changed our tape drive, because it started to fail to write on
>>> tape. I have changed it with the same model.
>>>
>>> After sostitution, amanda cannot recognise the tape, every day it
>>> give me error like "Not an amanda tape", and i have to amrmtape then
>>> amlabel the tape again.
>>>
>>> Is it possible to solve this problem?
>>
>>First, can you read the tape with "dd"?
>>Try to read the label:
>>
>> dd if=/dev/st0 bs=32k count=1
>>
>>Is the label you see correct?
>>
>>A frequent problem is blocksize difference.
>>
>>I work in variable blocksize.
>>On linux:
>> mt -t /dev/st0 defblksize 0 # add this in /etc/rc.*/* somewhere
>> mt -t /dev/st0 setblk 0 # or this just before handling tape
>>
>>If your tapes were written with a fixed blocksize, you should use that
>>value again (or relabel the tapes, and switch to variable blocksize).
--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
99.35% setiathome rank, not too shabby for a WV hillbilly
Yahoo.com and AOL/TW attorneys please note, additions to the above
message by Gene Heskett are:
Copyright 2005 by Maurice Eugene Heskett, all rights reserved.
|
