so, I installed a c6 system offsite today, had to do it in a hurry. box has 2 disks meant to be mirrored... I couldn't figure out how to get anaconda to build a LVM root on a mirror, so I ended up just installing a /boot and vg_system on sda and raid it later.
every howto I find for linux says to half-raid the OTHER disk, COPY everything to it, then boot from it and wipe the first disk and then bond it as a mirror of the 2nd. Thats kind of ugly.
in solaris, you can tell it that your existing partition is half of a mirror, update /etc/vfstab, then reboot, and then join a mirror to it. this seems much cleaner to me than copying everything.
I tried to do this the solaris way, and at the first step, am told...
# mdadm --create /dev/md0 --level=mirror --raid-devices=2 /dev/sda2 missing mdadm: cannot open /dev/sda2: Device or resource busy
/dev/sda2 contains the LVM root vg...
so... I'm thinking I''ll boot a rescue system from usb, create the half mirror, then reboot to the incomplete raid and add mirror /dev/sdb2
will the VG be found on /dev/md0 instead of on /dev/sda2 ? if so, is there any other reason this won't work?