Switching hardware between AIX partitions

You know the problem: you have one of these black pSeries POWER-boxes running VIO as virtualisation management layer. So far, so good. But this box has only one optical drive and you have to switch it from one AIX LPAR to another. The (virtual) hardware switching with eg the VIO web interface is no problem, but how do I tell the LPARs this change?

It is done by using the device management tools.
Assume that machine A currently owns the CD drive cd0, and machine B wants to have it:

1. umount /dev/cd0 on machine A
2. deactivate the device on machine A: rmdev -l cd0
   
3. or as alternative remove the device rmdev -dl cd0 , but be careful, because this removes also all device configurations (no problem for a CD drive, but not so good for eg a network interface card!)
4. do the (virtual) hardware switch using VIO web interface or something similar
5. activate the CD drive on machine B: cfgmgr (this runs the configuration manager, that automatically detects and configures the "new" hardware)
6. now you can use the hardware on machine B - in our case we will mount the CD-ROM: mount -v cdrfs -o ro /dev/cd0 /mnt