You can see the attributes set on your ASM diskgroups in 2 ways, via the view v$asm_attribute
SQL> select a.name, b.name, b.value from v$asm_attribute b, v$asm_diskgroup a where a.group_number=b.group_number and a.name='DATAX6C1' ;
Or via asmcmd and the lsattr
grid@sc7ach00pd00-d1:~$ asmcmd ASMCMD> cd DATAX6C1 ASMCMD> lsattr -G DATAXC1 -l
Attributes you might want to pay attention to in an Exadata environment are
If you manually create a diskgroup via asmca these attributes will not normally be set, and so you may want to go manually set them.
SQL> ALTER DISKGROUP DATAX6C1 SET ATTRIBUTE 'appliance.mode'='TRUE';
The attribute is set immediately, but based on my experience, it does not come into effect until the disk group has been rebalanced.
SQL> alter diskgroup DATAX6C1 rebalance power 2;