[Trinux-talk] Cloning Hard disk with Trinux

[<tb...@ti...>]

I admin a small ISP.  In the past few weeks, we have had three Seagate 
drives bite the dust (all the same model/batch), so the assumption is that 
the other drives are following soon.

Replacement drives are only about $100 at Fry's, but who wants to rebuild
a dozen machines.  The new drives are also bigger, so using dd to image
the drives would work, but I wouldn't get the benefit of the increased
drive space.

Enter Trinux ( Thank you Matt! ).

Here is how to clone your hard disks, and get the benefit of the increased 
capacity of the newer disk.  Note that I am actually cloning RedHat 
installations.  It doesn't matter.

First, make sure you have available the following packages:

diskutil
ext2tools
fileutil
modutil

and

fsmods   <-- from the pkg/2.4.5 folder

Open your computer case, and install your new hard disk.  Unplug the CDRom
(usually connected to primary on the second controller) and plug in your
old hard disk instead.

Boot Trinux from floppy and load the above packages.

The boot kernel doesn't support ext2 filesystems, so you must add the 
support via a module.

Install the ext2.0 module with the command:

insmod /lib/modules/ext2.o

Now prep your new hard disk with fdisk (or your favorite disk partion 
app).  I set my disks to:

fdisk /dev/hda

Partition 1  <-- /boot   250M (make this partition active)
Partition 2  <-- Swap    250M (change to type 82)
Partition 3  <-- /       Whatever remains.  As big as possiible

X86 boxes, and the ancient requirements that all bootable load modules be 
located in the first 1024 cylinders, need to have the kernels loaded in 
the first part of the disk.  This is why the separate boot partition.

Once you have the partitions set, format them with ext2 filesystems with 
the command:

mke2fs /dev/hda1
mke2fs /dev/hda3
and create the swap partition.
mkswap /dev/hda2

Be extra careful here, because if you put the disks in backwards, you 
could be formatting the old data...    To be really careful, don't 
plug in the old data disk until after you have formatted the new one.  I 
do this extra step when the data is critical, and I don't have backups....

Now make two mount points..

mkdir /new
mkdir /old

mount up the old disk with:

mount /dev/hdc3 /old
mount /dev/hdc1 /old/boot

It might be prudent to e2fsck them first...  Then..

mount up the new partitions with:

mount /dev/hda3 /new
mkdir /new/boot              <-- need to create new mountpoint for boot
mount /dev/hda1 /new/boot

now cd to /old and execute the following:

find . -depth -print | cpio -pmduv /new

This will copy the contents, file by file from the old disk to the new 
one.  The -depth parameter helps insure that all directories get chowned 
and chmoded properly, otherwise, cpio will make them owned by the same 
owner as the first file it writes to the folder. (It is faster if you 
leave off the "v", but then you stare at a prompt for a long time..)

After the file copy is complete, then you need to run lilo, or whatever 
bootloader you are using.  I use the command:

cd /new/etc
lilo -r /new

The "-r /new" causes lilo to do a chroot to /new before running lilo, 
which is required since you have your new root partition mounted on /new, 
not the root.  Lilo also requires that the disk being bootstrapped be 
connected to the controller it will boot from.  This is why the new disk 
needs to be put in place on the primary controller, and not the other way 
around.

One last caveat..  RedHat 7.0 is using disk labels in the /etc/fstab file 
instead of the good old devs.  I just edit the labels out and replace them 
with /dev/hda1 and /dev/hda3 in the fstab file.  Or you could label the 
partitions, but I didn't figgure out how to do that yet...

sync and unmount the disks.

Shut down the system and remove the old disk.  Plug the CDRom back on and 
boot her up...  Back online with all configs, log files, etc, just like 
when you shut it down.

I hope this helps someone out, somewhere...  I have been using this method 
for about a dozen years, since my days at Locus.  cpio is the only app I 
have found that makes perfect mirror images (devs, procs and all), but 
only if you use -depth with the find...

I noticed ntfs tools are available.  This might work with Windows disks 
too.  I haven't tried.

And Thanks again to Matt, for putting up find and cpio on the pkg site for 
me.

-- 
--------------------
Timothy Burt
Internet Specialist