I have installed centos 5.1 on ich9do with two identical sata harddisks installed. bios raid is configured as raid 1.

if one disk failed, how to recreate the raid disk set and recover all data to the new HDD?

below is the info from dmraid
[root@dhcppc2 ~]# dmraid -r
/dev/sda: isw, "isw_bcccehjebj", GROUP, ok, 625140333 sectors, data@ 0
/dev/sdb: isw, "isw_bcccehjebj", GROUP, ok, 625140333 sectors, data@ 0

[root@dhcppc2 ~]# dmraid -s
*** Group superset isw_bcccehjebj
--> Subset
name : isw_bcccehjebj_Volume0
size : 625133824
stride : 128
type : mirror
status : ok
subsets: 0
devs : 2
spares : 0