[plug] backups

[Peter F Bradshaw]

Hi Bill;

On Fri, 21 Apr 2006, W.Kenworthy wrote:

> Hi Peter, this is the way I decided to go: been running for awhile.  I
> see you have niced the bzip, I'll do that next time as it certainly pegs
> out the processor.

It does run slower than it should - not a problem usually because I'm
asleep at the time. The problem is that bzip2 works by taking a large
block of tar output, compresses it, and then shoves the output across
the network before taking another block. From time to time I've looked
for something that might be used to buffer the bzip2 output. It would be
quite easy write a simple utility which had a "ring buffer" and
implemented stdin and stdout asynchronously. If only I was not so lazy.

I should have pointed out a limitation for the record. There is a
potential problem with tar. It can only accept pathnames of less than
a certain length (100 chars from memory). We actually transfer deeply
nested source trees as bziped shar archives for this reason.

>
> BillK
>
> On Fri, 2006-04-21 at 11:53 +0800, Peter F Bradshaw wrote:
> > Hi Bill;
> >
> > On Fri, 21 Apr 2006, W.Kenworthy wrote:
> >
> > > Whats a good way to do a whole disk backup ready for a partial restore
> > > (hunt and pick).  My thoughts are to scp / down a pipe into a tar.bz2 on
> > > a server with room.  Or alternatively, dd it into a compressed loop
> > > mounted file (how to create such a beast?).  This might be more
> > > convenient.
> >
> > For my regular backups I run a script which uses constructs like:
> >
> > tar -cvpf - -X backup.exclude / | nice bzip2 -cv | ssh backup-machine " cat > full-system.backup.tar.bz2"
> >
> > This script runs in a "signed enviroment" (see ssh-agent, ssh-add) but
> > that's not necessary if you do not mind typing the pass phase every time
> > ssh is run.
> >
> > >
> > > My laptop is dying looks like being replaced, and rather than the
> > > config/work area backups I am running with on a day to day basis, I am
> > > looking to do a full one 'just in case' I have missed something
> > > important.
> > >
> > > BillK
> > >
> >
> > Cheers
> >

Cheers

-- 
Peter F Bradshaw, http://www.exadios.com, ICQ 75431157 (exadios).
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