Re: [Dump-users] Problems restoring on FC6

[Peter V. <pe...@wn...>]

Stelian,

Thanks for the reply.  In response to your suggestions:

>In your case, I see only two possibilities:
>1) there is a hardware incompatibility between the two drives.
>2) there is a software (driver) incompatibility between the two drives.

>In order to rule out 1), you need to physically swap the tape drives =
(or
>install RH9 on the new machine on some removable media).

I am going to install the new drive in the RH9 system and see if I=20
can read old tapes. =20

For 2) I guess you should ask for help the maintainer of the SCSI tape
driver (Kai Makisara), either directly or on the scsi mailing list.

Kai Makisara replied to my query just today.  His response=20
to my questions follows:

> I'll insert a tape into the FC6 PC that was created on the RH9 PC
> and issue this command :
>=20
> " mt -f /dev/nst0 fsf 1"
>=20
> And get back an error      "/dev/nst0: Input/output error"
>=20
> and in dmesg I get :      "st0: Current: sense key: Medium Error
>                                    Additional sense: Unrecovered read =
error"
>=20
This comes from the drive. It can't read the tape. This is not a problem =

you can solve by software.

> So just a basic position of the tape fails. However
> "mt -f /dev/nst0 rewind"  yields no error.
>=20
Rewind does not need to be able to read much of the tape.

> The versions of /bin/mt are different.  RH9's is 0.7 and FC6 is 0.9b
> but from looking at the man pages for mt, st and the README file
> for the mt v0.9b I don't see any significant modifications or default
> differences.
>=20
The mt versions don't matter.

> What's also very interesting is that if I create multiple dumps on the
> FC6 PC I can restore from the FC6 PC.  Positioning the tape
> also works.
>=20
> I'd like to get to the bottom of this - can you offer any suggestions =
on
> how to proceed?  Are there any "mt" commands that could be helpful?
>=20
It seems that the drive reading the tape can't raed what the other drive =

has written. The DDS drives are quite well compatible. So, I would say=20
that either the drive that has written the tape or the drive reading the =

tape is broken. If it is an alignment problem in the drive, it is =
probable=20
that the drive can read tapes written by the same drive but has=20
difficulties with tapes written by other drives.

Kai

~~~~~~~~


I'll post my results after swapping the tape drive in case there is =
interest.

Thanks to all,
Peter