- Data ONTAP 8.2 7-Mode
- Data ONTAP 8.1 7-Mode
- Clustered Data ONTAP 8.2
- Clustered Data ONTAP 8.1
- Data ONTAP 7 and earlier
All new Data ONTAP 7-Mode and clustered Data ONTAP aggregates are created as 64-bit by default. However, in earlier systems, or during migrations, 32-bit aggregates can be found. In order to have aggregates larger than 16 TB, convert a 32-bit aggregate to 64-bit; if this is not a requirement, there is no reason to convert a 32-bit aggregate to 64-bit.
64-bit aggregates require more free available space than 32-bit aggregates because the block pointers are larger. You will not able to start aggregate conversion if a volume is near full in the aggregate and the upgrade process will abort if the volumes become full during the upgrade process.
The aggregate conversion is non-disruptive; however, there might be a slight performance hit. It is not possible to estimate how long it will take to complete the conversion, as well as the performance impact; this depends on system usage.
The commands are the different in Data ONTAP 7-Mode and clustered Data ONTAP versions. Data ONTAP 8.0 and later is required to support 64 bit aggregates. In all versions prior to clustered Data ONTAP 8.2.1, 64-bit aggregate conversion is triggered by adding a single disk to an aggregate that is 16 TB; in 7MODE prior to 8.1.4P4, you must have enough disks to exceed 16 TB before you can upgrade the aggregate to 64 Bit. In clustered Data ONTAP 8.2.1+ and 8.1.4P4 7-Mode, you are able to perform the conversion without adding disks.
Data ONTAP 8.3+ no longer supports 32 bit data and before upgrading to this version, you will be required to upgrade all volumes to 64 bit. The Upgrade Advisor will contains steps on this. When migrating from 7MODE to CDOT, you will need to upgrade 32 bit volumes to 64 bit before the TDP snapmirror relationship transfers will work.
There are no special considerations if the root volume is on the same aggregate that needs to be upgraded to 64 bit. The same commands and procedures will work.