How To Resize An ASM Disk? (Doc ID 470209.1)
1) Please backup the database(s) contained inside the associated diskgroup.
2) Then shutdown the databases contained inside the associated diskgroup.
3) Dismount the associated diskgroup to verify no client database connections are accessing this specific diskgroup:
SQL> alter diskgroup <diskgro
asm content.type
content.type=date
Decreased likelihood that multiple failures would impact disk groups with different content
