sqlplus / as sysasm

SQL> CREATE DISKGROUP DATA NORMAL REDUNDANCY
2 FAILGROUP a1 DISK
3 '/dev/data1_1' name a1data1,
4 '/dev/data1_2' name a1data2
5 FAILGROUP a2 DISK
6 '/dev/data2_1' name a2data1,
7 '/dev/data2_2' name a2data2
8 ATTRIBUTE 'au_size'='1M',
9 'compatible.asm' = '11.2',
10 'compatible.rdbms' = '11.2',
11 'compatible.advm' = '11.2';

Diskgroup created.