[geeks] Copy a linux disk

[Joshua Boyd]

On Sat, May 27, 2006 at 10:38:53PM -0500, Doug McLaren wrote:

> systemimager is built on rsync, and is quite convenient to work with,
> but it's got it's own share of quirks.
> 
> I'm pretty sure that rsync can handle special devices -- block and
> character devices anyways -- just fine, as such support would be
> needed for systemimager.

I'm using rsync now to maintain sync between various flash cards and two
copies on disk (the first disk copy is just a copy, and the second disk
copy has extra stuff to be a build environment).

Initializing new cards is done buy dd'ing an image now that the layout
is fairly stabilized.  This is very slow, but also requires less user
intervention. 
 
> gnu tar can handle them as well, on all the *nixes, and has for over a
> decade, and it's what every Linux I've ever seen comes with.  It used
> to be that cpio's big strength over tar was that it could do special
> devices, but gnu enhanced tar nicely.

> Of course, Linux has often required some grub/lilo magic, so perhaps
> it's just that I've gotten more used to that.

grub is starting to get annoying.  I can't figure out how to convince it
that while the drive it is blessing is currently hdc that I really want
it to bless that drive as if it was to be hda, since I'm moving it as
soon as I power down.
 
> In any event, I suspect that Joshua's problem was that when he was
> using cpio, devfs/udev or it's equivilent was mounted (and it had to
> be, for the system to be usable) and this `covered up' the entries
> that were in /dev previously, which were needed for the boot process.

I don't think I was doing that.  I was booting from a LiveCD, and trying
to cpio the internal harddrive to a flash card in an IDE adapter.  I
don't think the LiveCD would have been masking the files in /mnt1/dev.
 
> Often the specific device names are different between different
> setups, and more than one setup can be required in the process of
> booting up, which can cause MUCH confusion, especially when using
> something like systemimager (those quirks I was mentioning ...)

Or when no two systems around here have the same NIC and I don't have the
target system in hand yet.  *Grumble*grumble*grumble*.  Currently it
looks like we will be shipping e100, e1000, tulic, realtek, and 3com
drivers in a machine that should absolutely never be used on anything
other than one specific SBC.  But, I'm not volunteering to go back and
remove the extras now.  We are supposed to be shipping on Tuesday.

-- 
Joshua D. Boyd
jdboyd at jdboyd.net
http://www.jdboyd.net/
http://www.joshuaboyd.org/