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Creating a Flash Pool aggregate using SSD storage pools

You create a Flash Pool aggregate with SSD storage pools by enabling the feature on an existing aggregate composed of HDD RAID groups, and then adding one or more SSD storage pool allocation units to that aggregate.

Before you begin

About this task

If you want the RAID type of the cache to different from that of the HDD RAID groups, you must specify the cache RAID type when you add the SSD capacity. After you add the SSD capacity to the aggregate, you can no longer change the RAID type of the cache.

After you add an SSD cache to an aggregate to create a Flash Pool aggregate, you cannot remove the SSD cache to convert the aggregate back to its original configuration.

Steps

  1. Mark the aggregate as eligible to become a Flash Pool aggregate: storage aggregate modify -aggregate aggr_name -hybrid-enabled true
    If this step does not succeed, determine write-caching eligibility for the target aggregate.
  2. Show the available SSD storage pool allocation units:storage pool show-available-capacity
  3. Add the SSD capacity to the aggregate: storage aggregate add aggr_name -storage-pool sp_name -allocation-units number_of_units

    If you want the RAID type of the cache to be different from that of the HDD RAID groups, you must change it when you enter this command by using the raidtype parameter.

    You do not need to specify a new RAID group; Data ONTAP automatically puts the SSD cache into separate RAID groups from the HDD RAID groups.

    You cannot set the RAID group size of the cache; it is determined by the number of SSDs in the storage pool.

    The cache is added to the aggregate and the aggregate is now a Flash Pool aggregate. Each allocation unit added to the aggregate becomes its own RAID group.
  4. Optional: Confirm the presence and size of the SSD cache: storage aggregate show aggr_name
    The size of the cache is listed under Total Hybrid Cache Size.