Thanks! It all worked really great, I had to correct only one typo: > device /dev/sda (hd0) into this: device (hd0) /dev/sda I have debian etch here, and I didn't have to rebuild initrd kernel. Also I didn't have to disconnect hda drive, I just selected a different boot device during boot (without even going into bios, or opening the case). In fact.. the only "trouble" I had here is that I needed to connect a PS2 keyboard to this box ;-) (it's a just a backup machine) And now I have a full RAID1 array. Now just two questions: 1. when I `shutdown -r now` I see a worrying message at the end: Stopping array md2 .... done (stopped) Stopping array md1 .... done (stopped) Stopping array md0 .... failed (busy) Will now reboot md: Stopping all md devices md: md0 still in use <reboots> Is that ok ? 2. Will grub update all drives automatically, for instance when I will upgrade kernel by 'aptitude upgrade'? Or do I need to repeat your grub instructions each time a new kernel is installed? thanks again! -- Janek Kozicki | - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html