[ale] writing to tape

[Geoffrey]

Greg Freemyer wrote:
> 2010/2/2 Björn Gustafsson <bg-ale at bjorng.net>:
>> On Mon, Feb 1, 2010 at 10:31 AM, Geoffrey <lists at serioustechnology.com> wrote:
>>> Greg Freemyer wrote:
>>>> What's your command line including pipes.
>>> ssh servername "tar -cf - $BackupThis" | dd bs=10k of=/dev/nst0
>> I don't know if it works with GNU tar, but you might want to try the
>> -B switch and/or to set `-b 20' to explicitly match the dd blocksize.
>> (20 should be the default though.)
>>
>> After quickly checking the GNU tar manpage, it seems to indicate that
>> -B only works for reads, but it might be worth a try anyway.
>>
>> --
>> Björn Gustafsson
> 
> tar is not the problem.  Its whatever the interconnect is between the machines.
> 
> It is not keeping up with the tape drive so dd is stalling out on the
> input from the comm channel and creating partial blocks on its output.
>  dd is just not really a good tool for this use case.
> 
> I've come across similar issues in the past.  My solution was to us
> mbuffer as I said in a previous email.
> 
> I think this is what I used <http://www.maier-komor.de/mbuffer.html>
> but it was years ago.  Back then it was not really well supported and
> I had to patch in some fixes..  To my surprise it is now in the
> opensuse distro, so maybe others as well.

Seems it's well maintained, last update dec 27 of last year.  I'll check 
it out, thanks.

> 
> Greg


-- 
Until later, Geoffrey

"I predict future happiness for America if they can prevent
the government from wasting the labors of the people under
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