Tim wrote:
On Thu, 2007-08-16 at 08:11 -0600, Karl Larsen wrote:
Hi Tim, I think you suffer from a fear of "fisk" :-) Yes you
do need to be careful. Look at it this way:
No, I don't. Whatever "fisk" means... ;-)
If your going to make a software raid-1 on Linux you must use a
root Terminal. A root Terminal is capable of deleting your entire
Linux! :-(
This paper is not for a person who has no knowledge of root and
what it can do. You need to know the basics. I will add a place where
they must show this basic knowledge or not try to do raid-1.
Now you're going off on a tangent. The only disclaimer needed, as
already mentioned by us, is to point out changing drive structures is
potentially destructive. Make backups before altering a pre-existing
system.
With his approach he doesn't change the existing drive until the new one
is known to work. The potential failure mode is that you get the wrong
device name for the fdisk or mke2fs steps. There's not much sense in
trying to describe Linux device names for anything but hd? devices since
they are essentially randomized, so the user will be on his own there
regardless of what you write anyway.
What I see you doing, and everything you've said leads to this
conclusion: You're making the classic mistake of over-simplifying
something to the point that you completely ignore necessary aspects.
It really will boil down to a very simple set of steps:
fdisk the new target partition
mdadm create a raid device with a missing mirror
mkfs a filesystem on the md device
mkdir a temporary mount point
mount the md device on the tmp mount point
copy the files from the old filesystem to the new.
repeat for all filesystems
either label the new filesystem to match the old or fix fstab/grub.conf
install grub on the new disk
swap disks
reboot
Once it all works with the new disk, fdisk the old one to match if it
didn't already and mdamd --add the mirror partitions.
The tricky parts are dealing with what happens if you make duplicate
filesystem labels and making the new drive bootable. But those can be
fixed with a rescue-mode boot.
--
Les Mikesell
lesmikesell@xxxxxxxxx
