Creating a study to decommission hosts

Decommission selected hosts and view the impact of distributing their guests to the selected new or existing target environment. Select Decommission Hosts after selecting data for your virtualization study to display the Decommission Hosts - Select Hosts page.

To select hosts to decommission

1. Select a Study Profile from the Study Profile drop-down list.
2. Use any of the predefined filters from the Target Filter drop down list or create your own filters to dynamically narrow down and select consolidation candidates. To create a custom computer filter, select Create your own Host filter. For more information, see Creating-computer-filters-for-a-virtualization-study.
3. Select the existing target environment to use as the baseline for the growth from the list of hosts shown in the Target Virtual Hosts table.

Decommission Hosts - Select Hosts page

To view the fields in the Target Virtual Hosts table

The following table describes the columns in the Target Virtual Hosts table:

Column	Description
Virtual Host	The system name of the virtual host.
Type	The type of virtual host.
Description	Type a description for the virtual host.
Cluster	Name of the corresponding cluster.
Nbr of Guests	The number of guests running on the virtual hosts. This value is shown in bold type if it is equal to the Maximum Guests per Host value shown in the Virtualization Parameters section of the Consolidation Summary.
Perf Rating	The SPECint rating of the system. This column is blank if the computer is a guest computer. The value is expressed in the rating selected in the Performance Rating Basis of the Settings page.
Avg CPU Util (%)	The percentage of CPU capacity currently in use.
Mem Cfg (GB)	The total amount of memory configured for the virtual target.
Avg Mem Util (GB)	The average amount of memory in use during the date range specified in Time Period.
Storage Used (GB)	Disk storage used by the system. This field will be available for applicable platforms.
Total Storage (GB)	The total storage capacity available.
Assignment Action for Existing Guests	Use this option to specify how to handle the existing guests that are currently running on the corresponding virtual host. The options are: Move all for this study, Ignore all for this study, and Set for each guest.
View Guests	Click View Guests to review and change the guest assignments for individual hosts. By default, the guests currently running on the existing virtual hosts will be included in the consolidation study. You can also view key performance statistics and utilization graphs for each guest. For details, see Viewing the guests on an existing virtual host.

Click Next to display the Decommission Hosts - Select Targets page.

The Decommission Hosts - Select Targets page is displayed.

To select target virtual hosts

Follow the steps given below to select the targets for the study:

1. Type the Study Name and Description for the study.

2. Click Set Affinity to specify any affinity relationships for the guests. For example, if one of the guests is planned as a backup system for another guest, you would not want both of those guests to reside on the same virtual host. See Setting an affinity relationship for computers.

   Success

   Tip

   Setting affinity relationships provides additional information about the servers in the study that Server Sizer cannot determine from the collected data, such as whether one server acts as a backup server for another.

3. Select the target virtual hosts for the study. You can create a new virtual host for the study if you are planning to upgrade or buy new hardware, or use existing virtual hosts.
   • Select the Use Existing Virtual Hosts option to specify the existing virtual hosts from which the guests will be decommissioned.
      By default, the guests running on these hosts are also included in the study.

   • Select the Create New Virtual Host option if you want the study to create one or more new virtual hosts (using the physical configuration shown in the table) if additional hosts are required to effectively handle the decommissioning.
     Click Change CPU Model to change the default configuration. For more information, see Changing the target hardware.

     Warning

     Note

     The Create New Virtual Host section is not displayed if you entered * as the value for one of the guests, for the purpose of projecting the number of copies that can be deployed on an existing target.

4. Click Advanced to define virtualization parameters such as the maximum number of guests allowed for target hosts (new or existing), as well as the amount of CPU overhead that will be used by the target host. You can also set thresholds for the maximum amount of the host server CPU and memory that can be used by virtual guests.
   Verify that the default settings from the Study Profile apply to your virtualization goals, or update the values. See Changing-virtualization-parameters-for-a-virtualization-study.
5. Click Next to display the results.

For information on the results page displayed, see Reviewing-virtualization-study-results.