Upgrade Hard Drive

[Michael Wiktowy]

On Jan 9, 2008 2:07 PM, Tom Spec <samag70-ignore at yahoo.ca> wrote:
>
> I am planning to move from one HD to another I need a bit of feedback.  I am
> partitioned as follows:
>
> sda1 /boot (Linux Partition) 256M
> sda2 LVM PV (Linux LVM Partition) 20G
>
> I was planning to.....
>
> 1) attach the new HD
> 2) boot to a rescue CD
> 3) partition the new HD exactly how the old one is
> 4) dd if=/dev/sda1 of=/dev/sdb1
> 5) dd if=/dev/sda2 of=/dev/sdb2
> 6) make the new HD bootable
> 7) disconnect the old HD
> 8) boot
>
> My questions...
>
> - Is this basically the right procedure?
> - Do I need to boot to the rescue CD or would single user (or emergency)
> mode be good enough (in step 2)?
> - Exactly what steps are required to "make the new HD bootable"?
> - Is there a way for me to make the old hd "unbootable" so I can leave it
> in, but make sure it's the new one that boots?

I have done this a couple of times but not with LVM partitions, just
regular ones but the drive did contain a Windows partition. A few
tips:

- in your dd commands, use the blocksize (bs=) parameter also since it
will speed up the process *a lot*. I usually set it to bs=8M since
that is the typical size of a HDs cache memory.

- you can skip the whole making the exact same partition step and
making things bootable just by using the whole drive device rather
than the separate partition devices (i.e. if=dev/sda of=/dev/sdb)
since the partition table and MBR will get mirrored over in the first
1024 bytes on the drive

- quadruple check the if= and of= targets ... then check them again
... there is no quicker way of hosing all your data than getting those
reversed.

- don't try to boot to one of the drives with both drives in the
machine ... bad things will happen with identical drive/LVM labels.
Once you have done the mirror, take the old drive out, put the new
drive in its place and then boot. Once everything is OK and a fsck is
fine, you can boot to a CD and change all the labels on the old drive
to make sure they don't conflict when you mount them . From the CD you
can non-destructively resize the new partitions to take up more space
on the new drive (as I am assuming that is why you are moving to a new
drive).

Good luck.

/Mike