SQL> select GROUP_NUMBER,NAME from v$asm_diskgroup;

GROUP_NUMBER NAME
------------ ------------------------------
           1 DATA
           2 FRA

SQL>
SQL> select GROUP_NUMBER,name,PATH from v$asm_disk;

GROUP_NUMBER NAME                           PATH
------------ ------------------------------ -------------------------
           1 T1_ASM01                       ORCL:T1_ASM01
           2 T1_ASM02                       ORCL:T1_ASM02
           0                                ORCL:T2_BACKUP01
           0                                ORCL:T1_ASM04
           0                                ORCL:T1_ASM03
           0                                ORCL:T1_ASM05

6 rows selected.

SQL> !
/home/oracle > /etc/init.d/oracleasm listdisks
T1_ASM01
T1_ASM02
T1_ASM03
T1_ASM04
T1_ASM05
T2_BACKUP01
/home/oracle >