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Use Case Study: Using Active System For VMware Cluster Environment Configuration
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Create Cluster
Before adding hosts to the vCenter environment, create a cluster for these hosts to reside in. Creating
a cluster will provide the ability to pool the resources of all of the added hosts. Two or more iSCSI
volumes will be utilized for the clusters datastores which will be used to store the virtual machines
hosted by the cluster. The cluster will be created and configured to provide HA, DRS, and fail-over
capabilities so that if one of the hosts is lost, the virtual machines on that host may be migrated to
other healthy ESXi hosts within the cluster.
To create a cluster, go into your vCenter Server instance, right click on the datacenter you wish to
place the cluster in, and select “New Cluster”. vCenter Server will walk you through a wizard to create
your cluster. In this example both HA and DRS have been enabled for the cluster. This will provide the
ability to detect failures and provide rapid recovery for any deployed virtual machines. DRS will give us
the ability to manage hosts as an aggregate pool of resources and will allow vCenter Server to manage
the assignment of virtual machines to hosts automatically to balance the load and enforce any resource
allocation policies that are created. The cluster will be configured to be fully automated to attain the
best use of resources. In this example power management for the cluster was not enabled, but these
settings can be adjusted as needed for your specific cluster needs.
Continuing through the New Cluster Wizard, ensure that host monitoring is enabled. Keep the default
settings for Admission Control and Enable the setting which determines the amount of cluster capacity
that is reserved for VM failover. In this cluster the Admission Control Policy setting was configured to
tolerate 2 host failures. This number can be adjusted depending on the number of hosts in your
environment and the specific needs of your cluster. The default settings were selected for the Cluster
VM restart policy and Host Isolation response. For VM Monitoring only monitoring VMs was selected and
the monitoring sensitivity was set to “High”. EVC was disabled for this cluster. These settings again are
chosen for example purposes and may be modified to meet the specific needs of the cluster you
require. For more information on VMware Cluster creation refer to the VMware documentation and best
practices for clusters.
Once vCenter Server has finished completion of you cluster creation you are ready to add hosts to the
cluster.
Add Hosts to Cluster
Once you have successfully configured the management access settings (password and IP information)
for your hosts and created your cluster in vCenter Server, you are ready to add your hosts to the
VMware cluster.
You will need the management IP Addresses and credentials for all the ESXi hosts you wish to add to
your cluster. To add a host, right click on the cluster you just created and select “Add Host”. Enter the
credentials and IP Address information for the host you wish to add. Enter any licensing information
required for the ESXi host. Choose whether you will enable lockdown mode for your ESXi hosts, which
will prevent remote users from logging into the host. Determine host to manage the resource pools for
the host, and complete the wizard to add the host.
This process should be repeated for each host you configured via Active System Manager. Once you
have added all hosts to the cluster they are available for configuration of the remaining networking and
storage needed to support the virtual machines which will be placed in the cluster.