How to add the mirror partition to a RAID 1 set with Vinum

Hello,

I am running FreeBSD 5.1 and would like to have all my partitions of by
FreeBSD installation mirrored (RAID 1). So I followed the steps form the
FreeBSD handbook (the part called Installing FreeBSD on Vinum). So far I
got my first disks partition into the RAID 1 set, now I have a second
hard disk which needs to be part of the RAID 1 set... as you can see
right now the configuration for the root (/ partition) looks like this:


# vinum l -rv root
Volume root: Size: 536870912 bytes (512 MB)
State: up
Flags: open
1 plexes
Read policy: round robin
Plex root.p0: Size: 536870912 bytes (512 MB)
Subdisks: 1
State: up
Organization: concat
Part of volume root

Subdisk root.p0.s0:
Size: 536870912 bytes (512 MB)
State: up
Plex root.p0 at offset 0 (0 B)
Drive rootdev (/dev/ad0s1h) at offset 1073733632 (1023
MB)


Unfortunately from this point I am lost. What is the next step ? Do
I need to configure my second disk with exactly the same disklabel as my
first disk ??

Thanks for your help in advance

Regards