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Table Of Contents
3 (Optional) Configure advanced options.
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No recommendations until utilization difference between source and destination is: Use the slider
to specify the space utilization difference threshold. Utilization is usage * 100/capacity.
This threshold ensures that there is some minimum difference between the space utilization of
the source and the destination. For example, if the space used on datastore A is 82% and
datastore B is 79%, the difference is 3. If the threshold is 5, Storage DRS will not make migration
recommendations from datastore A to datastore B.
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Check imbalances every: Specify how often Storage DRS should assess space and I/O load
balancing.
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I/O imbalance threshold: Use the slider to indicate the aggressiveness of I/O load balancing.
Lowering this value makes I/O load balancing less aggressive. Storage DRS computes an I/O
fairness metric between 0 and 1, which 1 being the fairest distribution. I/O load balancing runs
only if the computed metric is less than 1 - (I/O imbalance threshold / 100).
4 Click OK.
Datastore Cluster Requirements
Datastores and hosts that are associated with a datastore cluster must meet certain requirements to use
datastore cluster features successfully.
Follow these guidelines when you create a datastore cluster.
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Datastore clusters must contain similar or interchangeable datastores.
A datastore cluster can contain a mix of datastores with different sizes and I/O capacities, and can be
from different arrays and vendors. However, the following types of datastores cannot coexist in a
datastore cluster.
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NFS and VMFS datastores cannot be combined in the same datastore cluster.
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Replicated datastores cannot be combined with non-replicated datastores in the same Storage-
DRS-enabled datastore cluster.
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All hosts attached to the datastores in a datastore cluster must be ESXi 5.0 and later. If datastores in
the datastore cluster are connected to ESX/ESXi 4.x and earlier hosts, Storage DRS does not run.
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Datastores shared across multiple data centers cannot be included in a datastore cluster.
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As a best practice, do not include datastores that have hardware acceleration enabled in the same
datastore cluster as datastores that do not have hardware acceleration enabled. Datastores in a
datastore cluster must be homogeneous to guarantee hardware acceleration-supported behavior.
Adding and Removing Datastores from a Datastore
Cluster
You add and remove datastores to and from an existing datastore cluster.
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