Managing different aspects of the storage to help satisfy different requirements is one of the purposes for NetApp ONTAP Disk Aggregates. In fact NetApp disk aggregates can be configured to support several configurations where requirements like security, backup and performance are different across various departments.
The previous article with regards to the NetApp storage for VMware was covering the default capabilities. As of NetApp ONTAP 9.4 in fact there is a built-in functionality operating as an Assistant and helping with pre-configured Disk Aggregates based on available hardware. The NetApp ONTAP simulator supports up to 4 disk shelves, 14 disks each for a total of 56. The purpose of this article and the next one is to provide a quick look at the main features and options available through the GUI using the System Manager. Also how to move and replace disks leveraging the command line.
As an interesting set of options when managing disks as part of the Aggregates it is also possible to operate on RAID Type (RAID4 or RAID-DP, the latter offers RAID 6 dual parity failure) and RAID Group size which specifies the number of disks that should be assigned from the shelves.
Overview of NetApp ONTAP Disk Aggregates
In System Manager > Storage > Aggregates and Disks > Disks view the summary and inventory sections showing the main info about the existing NetApp ONTAP Disk Aggregates.
When selecting a particular Disk Aggregate of course it is possible to review the main info and edit settings like the ability to create a SnapMirror relationship with a secondary NetApp ONTAP and replicate content on a storage level. This is a feature that can be used at many levels: DR scenarios, data protection, compliance and more. Dedicated articles to follow and cover these topics in more details. Within the disk aggregates configuration there are links to the Volumes, Disks and Performance stats with real-time IOPS and Throughput charts.
In the Edit settings it is possible to choose between RAID4 and RAID-DP. The latter offers a greater tolerance rate up to two drives at the same time. Interestingly for each group the System Manager also shows the current number of assigned disks marking the ones used for parity, data and empty slots along with the total size.
When moving from one RAID to another the wizard also provides info about the parity disks. For example when downgrading from RAID-DP to RAID4.
The new totals are now calculated over a total of 8 Disks.
Now considering this is a simulator and all disks effectively are emulated within the same VMware vmdk data file, really makes no difference in having additional disks for redundancy. Certainly it is interesting to explore these areas as well for better configurations. For example in this case the remaining disks could be used to create other aggregates for other purposes. For example separate storage tiers or even dedicated to core functions like primary storage for virtual infrastructure or even NAS shares for several departments.