[KLUG Members] backing up

[Dirk Bartley]

On Mon, 2001-09-10 at 18:19, Adam Williams wrote:
> >I am having a little trouble backing up.  I am using tar as follows:
> >tar -cvzpf /dev/st0 -T /root/backup/whattobackup
> >when I restore the files with :
> >tar -xvzpf /dev/st0 it restores and then hangs.  When I try backup and then
> >restore a small amount of data it completely hangs and fails on the restore. 
> >(control c stops the hang.)
> >The tape device is a 4mm dat.  Here is from dmesg
> >Vendor: SEAGATE   Model: DAT    06240-XXX  Rev: 8160
> >Type:   Sequential-Access                  ANSI SCSI revision: 03
> >Anyone have any ideas for why it is hanging at the end of long restores and not
> >restoring small backups at all?
> 
> No, but I had the EXACT same thing with the EXACT same tape drive. 
> Fought with it forever.  A little TLC and the tape drive started eating
> the tapes and the OEM swapped it out as a bad unit.  Works great now.

So I should try and get it replaced then eh?
Bummer!

> 
> >On a side note, for network backups of files on a host without the tape drive,
> >what is your preferred method.  I have been using tar and ssh with some luck as
> >follows:
> >tar -czp TEST* | ssh srv2 'cat > /BAI.unidata/BAI.accounts/TEST.tgz'
> >but this is done to a file and not to a tape device.  Is it perfectly acceptable
> >to do this
> >tar -czp TEST* | ssh srv2 'cat > /dev/st0'
> 
> No.  You should write to the tape drive with dd so you can set the block
> size.

so the command would look like
tar -czp TEST* | ssh srv2 'cat | dd of=/dev/st0 bs=32k

what block size should I use?

Then would I still restore with
tar -xvzf /dev/st0  ????

> 
> >I also noticed from man tar that you can put a hostname before a tar.   -f,
> >--file [HOSTNAME:]F  What mechanism does this use and does it work/is it secure
> >like with ssh.
> 
> rmt via rexec.  It is secure only on a Kerberos network,  on "standard"
> networks it is hilariously not secure.
> 
Dirk