[plug] reinstall for new core hardware?

[James Devenish]

In message <3FF90E33.5040507 at leftclick.com.au>
on Mon, Jan 05, 2004 at 03:11:47PM +0800, Ben New wrote:
> Obviously there will need to be a kernel compile in there somewhere (in 
> my case, probably about 5 or 6 before I get it right) with the increased 
> number of processors and probably other things (?)
[...]
> What I'm mostly interested in is the boot process, the first time in the 
> new box.  Will the OS cope with the changes to the entire set of system 
> resources?  How automated will the process of detecting and installing 
> the correct drivers be?

Others have probably done this on Intel-based systems, so they do more
than just make the guesses that I'm about to make. Basically, I would
imagine that the kernel (i.e. Linux) is the issue here. (Given that the
CPU architecture is not changing, and assuming you're not advancing the
kernel by a multiple stable versions, then all of userland should be
executable.) I think that if you did a fresh install, you'd be putting
back exactly what was already -- the big exceptions are kernel options
such as SMP and the onboard Ethernet. (Also: if the new machine uses,
say, a USB keyboard whereas the previous machine didn't, you might need
to load some extra modules.) For things like the Ethernet interface, I
would expect Linux to map it to the same interface-name as in your old
machine (so there'd be no need to reconfigure userland). The sticking
point is whether the pre-compiled kernels have the drivers for the
built-in Ethernet in the first place. So...basically you might get away
with merely installing an SMP kernel package OR you might have to
compile/install support for your Ethernet.

> Will it be easier to just save the contents of /etc and a few other
> locations, wipe the rest of the OS and reinstall, then copy back /etc
> (etc)?

I think that things that would cause grief are the hard-coded values in
/etc, such as your hard drives, peripheral devices and XFree86 config
(if that is relevant to the machine). If the hard drives will be on
their bus in the same order as the old machine, then your existing
/etc/fstab might be correct anyway. So...I would suggest that if
anything is not portable, it's /etc and /var -- the locations you cannot
wipe :-)