[gentoo-user] Re: Moving the system from one disk to another

[Kerin Millar]

On 05/04/2010 00:51, Kacper Kopczyński wrote:
> Dnia 2010-04-04, o godz. 21:04:03
> Neil Bothwick<neil@××××××××××.uk>  napisał(a):
>
>> On Sun, 04 Apr 2010 20:35:11 +0100, Kerin Millar wrote:
>>
>>> Whichever way you go about it, ensure that no pseudo-filesystem or
>>> bind mounts are present within "/mnt/oldrootfs" at the time.
>>
>> Use the -x option with rsync to stop it descending into other
>> filesystems.
>>
>>
>
> AFAIK
>
> "mount --bind / /somewhere" and rsync'ing /somewhere/ instead of / would
> be more useful then "-x" option - stage1,2,3 has static /dev entries
> which should also be copied. Since udev mounts it with tmpfs, rsync
> with -x would skip those entries (static and from tmpfs).

Well, no, because my response was based on the fact that the duplication 
will be carried out from an alternate environment provided by a CD/DVD, 
as Meino clearly stated in the original post. Thus, bind mounts, 
pseudo-filesystems and chroots need not come into the equation 
whatsoever. Indeed, it's the very same concern that you express which 
resulted in my recommendation to avoid such shenanigans and keep it 
simple. Ergo, just mount the root filesystem - nothing else - and copy 
it as-is. Static /dev entries would be copied without issue, as would 
everything else. It really couldn't be simpler.

You post hinges on the notion that he would be performing the process 
while booted from the system he is duplicating, in which case your 
advice would, of course, be entirely sensible. Ergo, he would indeed be 
best advised to bind mount / to a temporary directory and use that as 
the source for the exact reasons that you mention. I personally would 
not recommend doing it under these circumstances but it can certainly be 
done (though I'd suggest dropping to runlevel 1 first).

Cheers,

--Kerin