LVM mirror

[Roy Marples <roy%marples.name@localhost>]

Hi list

I'm trying to upgrade my XEN host with a bigger disk.
My idea is to add the disk (via temporary USB as there's only 1 sata 
connector internally) configure it as a pv and add it as a mirror to the 
various lv groups i have to allow minimal downtime.

Following a guide here (not NetBSD), am I am this step:
lvconvert -m 1 /dev/tecmint_vg/tecmint_lv /dev/sda1

The command I'm trying are these:
lvm lvconvert -m1 /dev/mapper/vg0/vg0-name /dev/rsd0e
lvm lvconvert -m1 vg0/name /dev/rsd0e

But nothing works. There error I get is this:
  mirror: Required device-mapper target(s) not detected in your kernel
  Run `lvconvert --help' for more information.

This is not clear what options my kernel needs - it's almost a stock 
XEN0 config.

Any help or guidance welcome.

Roy