Para descobri os volumes de discos do ASM
[.grid_profile_root@host_oracle]# oracleasm listdisks
VOL1
VOL2
VOL3
VOL4
Para referenciar a que device ele representa
[.grid_profile_root@host_oracle]# oracleasm querydisk -p VOL1
Disk "VOL1" is a valid ASM disk
/dev/sdb1: LABEL="VOL1" TYPE="oracleasm"
[.grid_profile_root@host_oracle]# oracleasm querydisk -p VOL2
Disk "VOL2" is a valid ASM disk
/dev/sdc1: LABEL="VOL2" TYPE="oracleasm"
[.grid_profile_root@host_oracle]# oracleasm querydisk -p VOL3
Disk "VOL3" is a valid ASM disk
/dev/sdd1: LABEL="VOL3" TYPE="oracleasm"
[.grid_profile_root@host_oracle]# oracleasm querydisk -p VOL4
Disk "VOL4" is a valid ASM disk
/dev/sdf1: LABEL="VOL4" TYPE="oracleasm"
Na duvida de como esta configurado entre no sqlplus (ex : sqplus sys as sysdba) e consulte.
select * from v$asm_diskgroup;
ou
select group_number, name, total_mb,free_mb from v$asm_diskgroup;
Caso queira mapear os Volumes e discos :
/home/oracle
source .grid_profile
asmca
OBS :
Para aprender a configura discos asm indico fortemente :
http://aprenderoracle.com/2011/09/14/oracle-11-asm-grid-infrastructure-standalone-server/