[Discuss] How do you backup "/" with rsync?

[Alan W. Irwin]

On 2007-12-10 15:58-0800 John Blomfield wrote:

> I am not sure if this is what your looking for but I mentioned this before 
> when talking about recovering a damaged MBR.  I am assuming here that you 
> have backed up your /boot directory containing grub onto your external HD 
> along with everything else.  Then you need to recreate the MBR on the 
> external HD, so boot the system with a "Rescue CD" containing the usual Linux 
> utilities, which will find your two Linux installations, one on your internal 
> HD and one on your external HD. Then:
>
> # chroot /mnt/sysimage   - this gives you access to your installation image, 
> this name could be different with different distributions.( Fedora in this 
> case, the Fedora rescue disc works with any distribution)
>
> Then do the following:
>  # login
>   login: root
>  passwd: ******
>  # cd /boot
>  /boot# grub
>  grub > find /boot/grub/stage1
>  "response will be something like " (hd0, 0) (hd1, 0)
>  -what this tells you is that stage1 of grub has been found in two 
> partitions, one of which is the partition (hd0, 0) or sda1 your internal HD, 
> and the other partition (hd1, 0) or sdb1 your external HD.  Now type, ( note 
> the > is the Grub prompt)
>   > root (hd1, 0)
>  > setup (hd1)
>  > quit
>
> This will make your external HD bootable with a grub menu, as well as your 
> internal HD.  Now all you have to do is to change the BIOS to choose which 
> one you want to boot from.

Thanks, John, for that suggestion for setting the MBR of the external drive.

I have never used the grub command directly so I have two follow up
questions. Is it really necessary to be in rescue mode to set the MBR of the
external drive?  For example, can't you just invoke grub from the ordinary
command line as the root user?

Alan
__________________________
Alan W. Irwin

Astronomical research affiliation with Department of Physics and Astronomy,
University of Victoria (astrowww.phys.uvic.ca).

Programming affiliations with the FreeEOS equation-of-state implementation
for stellar interiors (freeeos.sf.net); PLplot scientific plotting software
package (plplot.org); the libLASi project (unifont.org/lasi); the Loads of
Linux Links project (loll.sf.net); and the Linux Brochure Project
(lbproject.sf.net).
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Linux-powered Science
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