Mon Jul 6 09:34:30 CEST 2009

conventional -> md

What I'm trying to figure out is how to convert a conventional disk
into an md one.  Starting with one partition hdb1 and trying to turn
this into /dev/md0 together with hda1.

This complains that hdb1 already contains a fs:

mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/hda1 /dev/hdb1

So, make sure the _live_ partition is added as missing.

mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/hda1 missing

The debian guide[1] talks about copying the data.  So it looks like it
is not possible to to copy the filesystem as a whole..

Maybe it is..  How to find out the size of a block device?  It can be
done using cfdisk /dev/md0... Apparently it uses 173 sectors.

So.. this probably rules out copying lvm partitions in the raw
format.. Means I need to do some repartitioning again, or figure out
how to use the lvm raid.

[1] http://www.google.com/search?q=rootraiddoc.97.html&hl=en&start=10&sa=N