Hi

We have a numbe of ageing SunOS boxes (Sparcstation IPX and ELC) which
are required for legacy support purposes.

The most likely failure mode of these boxes is the SCSI system hard
disks themselves, which inevitably will wear out and die at some time
in the future. The data and application programs are safely stored on
a server, and served via NFS, so we're OK on that front.

What is the best way to "image" these system drives, so that I can
quickly install get a system up and running again in the shortest
possible time.

I was thinking of just using "dd" to copy them to a raw image file, but
I'm not 100% sure how do do this correctly, or if there are any
pitfalls to be wary of.

Something like

dd /if=/dev/sd0c /of=blah.img

The "c" partition refers to the entire disk according to what the
"partition" part of the "format" utility is telling me.

But should I be referring to /dev/rsd0c, the "raw" device, instead of
/dev/sd0c or not ?

I was hoping there might bave just been a /dev/sd0 or /dev/rsd0 device
which just captured the whole disk drive but it appears not to be the
case (or am I missing something ?)

The other issue is what to do with any new disk drives I get.
Obviously not all of them will be the same as the SUN0424 drive that is
in there now, so if I use a larger drive, is it simpy OK to keep the
existing partition table and use dd to again write the disk from the
image (connecting the drive to another machine to do this) ?

Maybe I am best just to dump or tar the files back and forward, but
since this is a system boot disk, rather than just any old data disk,
I'm a bit more wary because obviously certain key parts of the SunOS
environment need to be in the right places for the boot ROM and SunOS
boot loader to do their jobs properly.

Any ideas appreciated, along with possible pros and cons of each
method.

I hope to eventually be able to use QEMU to emulate a Sun4 class box
and run all my applications on it in an emulated environment. At this
stage, QEMU + OpenBIOS doesn't fully support booting my old SunOS 4.1.4
environment (alas, shackled to the days before Solaris 2.5.x and later
versions came along due to the hundreds of legacy applications) , but
QEMU + OpenBIOS is getting closer all the time to realising that dream,
when I can finally turn the Sparcstation IPX and ELC boxes off forever.

Cheers

Jason