[rescue] Re: Re: Re: how to utilize multiple tape drives in the same library/silo with Amanda...

[Robert Novak]

I wrote: 
> > Well, for what Amanda is doing, there's no other way. It's writing the
> > tar/dump output to disk, then compressing it and putting it to tape (if I
> > recall correctly... maybe it's compressing the tar/dump output to disk,
> > then writing it raw to tape?)). You could try hacking it to do a
> > stdin/stdout split into blocks (kinda like what Networker used to do) but
> > that would be messy.
> 
On Mon, 22 Jul 2002, Ross Alexander wrote:
>
> Actually, amanda already does that. From man amanda:
> 
> 
> chunksize   		     Dumps larger than the speci-
> 			     fied size will be stored in multiple
> 			     holding  disk  files.   The  size of
> 			     each chunk will not exceed the spec-
> 			     ified  value.   However, even though
> 			     dump images are split in the holding
> 			     disk,  they are concatenated as they
> 			     are written to tape,  so  each  dump
> 			     image  still corresponds to a single
> 			     continuous tape section.

Hmmm. I wonder if it still requires the same amount of holding space but
can split it across filesystems/disks/whatevers. i.e. if I have a 100GB
filesystem and only 50GB of holding disk on two drives, will it chunk
them, and cycle through? How much patience would the protocol have if the
tape drive is slow (say, 4mm slow)? 

Might be worth poking into when I get a big drive hooked up. 

Rob

Robert Novak, Indyramp Consulting * rnovak at indyramp.com * indyramp.com/~rnovak
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