6.0.1

Table Of Contents
Cause
If the destination host explicitly specifies the virtual machine's swap file location as a datastore in the target
datastore cluster, the disks to be placed in that cluster do not form a single affinity group. Storage DRS
generates alternative placement recommendations only for a single item or a single affinity group.
Solution
Accept the single recommendation. To obtain multiple recommendations, choose a destination host that
does not specify that the virtual machine swap file location is on a datastore that is in the target datastore
cluster.
Applying Storage DRS Recommendations Fails
Storage DRS generates space or I/O load balancing recommendations, but attempts to apply the
recommendations fail.
Problem
When you apply Storage DRS recommendations for space or I/O load balancing, the operation fails.
Cause
The following scenarios can prevent you from applying Storage DRS recommendations.
n
A Thin Provisioning Threshold Crossed alarm might have been triggered for the target datastore, which
indicates that the datastore is running out of space and no virtual machines will be migrated to it.
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The target datastore might be in maintenance mode or is entering maintenance mode.
Solution
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Address the issue that triggered the Thin Provisioning Threshold Crossed alarm.
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Verify that the target datastore is not in maintenance mode or entering maintenance mode.
Troubleshooting Storage I/O Control
The Storage I/O Control troubleshooting topics provide solutions to potential problems that you might
encounter when using Storage I/O Control with datastores.
Unsupported Host Connected to Datastore
In the vSphere Web Client, an alarm is triggered when vCenter Server detects that a workload from a host
might be affecting performance.
Problem
The alarm Pre-4.1 host connected to SIOC-enabled datastore is triggered.
Cause
The datastore is Storage I/O Control-enabled, but it cannot be fully controlled by Storage I/O Control
because of the external workload.
This condition can occur if the Storage I/O Control-enabled datastore is connected to a host that does not
support Storage I/O Control.
Solution
Ensure that all hosts that are connected to the datastore support Storage I/O Control.
vSphere Troubleshooting
56 VMware, Inc.