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If you want to use the default report delivery mechanism, no additional component installations or
configurations are required.
To configure report subscriptions
1. In the Resources pane of XenCenter, select XenCenter > your-resource-pool.
2. In the Properties pane, click the WLB tab.
3. In the WLB tab, click Configure WLB.
4. In the left pane, click Advanced.
5. In the Report Subscriptions section, in the SMTP box, type the IP address or fully qualified domain
name (FQDN) of the email server that Workload Balancing will use to email the reports.
6. (Optional.) If you want to use Reporting Services as your report delivery mechanism, select the Use
Reporting Services for Report Delivery check box.
Choosing an Optimal Server for VM Initial Placement, Migrate, and
Resume
When Workload Balancing is enabled and you restart a virtual machine that is offline, XenCenter provides
recommendations to help you determine the optimal physical host in the resource pool on which to start
the virtual machine. Workload Balancing makes these placement recommendations by using performance
metrics it previously gathered for that virtual machine and the physical hosts in the resource pool.
Likewise, when Workload Balancing is enabled, if you migrate a virtual machine to another host, XenCenter
recommends servers to which you can move that host. This Workload Balancing enhancement is also
available for the Initial (Start On) Placement and Resume features.
In general, Workload Balancing functions more effectively and makes better, less frequent optimization
recommendations if you start (Initial Start On Placement and Resume) virtual machines on the servers it
recommends.
When you use these features with Workload Balancing enabled, host recommendations appear as star
ratings beside the name of the physical host. Five empty stars indicates the lowest-rated (least optimal)
server. When it is not possible to start or move a virtual machine to a host, an (X) appears beside the host
name with the reason.
To start a virtual machine on the optimal server
1. In the Resources pane of XenCenter, select the virtual machine you want to start.
2. From the VM menu, select Start on Server and then select one of the following:
• Optimal Server. The optimal server is the physical host that is best suited to the resource demands
of the virtual machine you are starting. Workload Balancing determines the optimal server based on
its historical records of performance metrics and your placement strategy. The optimal server is the
server with the most stars.
• One of the servers with star ratings listed under the Optimal Server command. Five stars indicates the
most-recommended (optimal) server and five empty stars indicates the least-recommended server.
To resume a virtual machine on the optimal server
1. In the Resources pane of XenCenter, select the suspended virtual machine you want to resume.
2. From the VM menu, select Resume on Server and then select one of the following:
• Optimal Server. The optimal server is the physical host that is best suited to the resource demands
of the virtual machine you are starting. Workload Balancing determines the optimal server based on
