Can Oracle's HCC work with v3 SNMP on the ZFS Storage Appliance or does it have to v1/2c?
SNMP is critical on ZFS Storage Appliances where HCC enabled tablespaces/databases reside on the ZFS storage. The database will go query the storage using an SNMP call to see whether or not it is a supported storage platform for HCC. If the storage platform is supported, HCC will be enabled for the storage. If the storage platform is not supported, HCC will not be enabled.
Additionally, the database only checks the storage once. It does not continually check the storage. This is sensible. However, if you make changes to the ZFS SNMP configuration, you must restart the database instance, so that the database will go out and check the storage again.