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A vSphere administrator is configuring a fully automated DRS cluster and determines that DRS is not balancing virtual machine workloads.
What condition could cause this behavior?
A. vMotion is not properly configured on the hosts in the cluster.
B. HA is not properly configured on the hosts in the cluster.
C. The DRS threshold is configured on the most aggressive setting.
D. Some of the virtual machines have been disabled from DRS.
Correct Answer: A
Explanation/Reference:
Explanation:
A: To enable the use of DRS migration recommendations, i.e. to effect the balancing of virtual machine workloads, the hosts in your cluster must be part of a vMotion network. And this vMotion network should be configured properly. vMotion is used to migrate virtual machines, and in this case into a DRS cluster. If vMotion was not properly configured on the virtual hosts in the cluster then DRS cannot balance their workloads effectively.
Incorrect Answers:
B: High Availability monitors are used to monitor the status of virtual machines in a cluster. it is in essence to make sure that virtual machines are available in case of the failure of another in a cluster. It is not the same as balancing the virtual machine workloads.
C: This threshold is also a measure of how much cluster imbalance across host (CPU and memory) loads is acceptable. This setting generates priority recommendations and only after a recommendation receives a priority level then the level is compared to the threshold that has been set whether automated or semi-automated to effect application of the recommendation. It is mentioned in the question that the DRS cluster is fully automated and thus this DRS threshold is not the problem.
D: When the hosts in a cluster becomes unbalanced DRS makes recommendations and migrate the virtual machines in the cluster. It is mentioned in the question that DRS is fully automated in this cluster thus the non-balanced virtual machine workload is not due to machines that have been disabled from DRS.
References:
https://pubs.vmware.com/vsphere-4-esx-vcenter/index.jsp?topic=/com.vmware.vsphere.resourcemanagement.doc_41/creating_a_drs_cluster/c_drs_cluster_prerequisites.html