Oracle 11g ASM: Changed permission policy ORA-15260

A new error has popped up in Oracle ASM administration...

"ORA-15260: permission denied on ASM disk group"

Problem is if you still connected as SYSDBA to ASM out of old habit from 10g you will get it.

The SYSOPER privilege permits the following subset of the ALTER DISKGROUP operations: diskgroup_availability, rebalance_diskgroup_clause, check_diskgroup_clause (without the REPAIR option). All other ALTER DISKGROUP clauses require the SYSASM privilege.

Just use the following to connect

sqlplus / as sysasm