VMware vRealize Operations Manager Step by Step (Part-4) Policy Configurations (Allocation Or Demand?)

Out of the box, the Default Policy in vRealize Operations is set to use an Allocation Capacity planning model for most Object types.

In many other circumstances, a better starting point would be to apply a Demand based policy for most Object types and resource dimensions.

We will go through how to make this changes and what difference they will make to the Capacity Planning Analysis results.

Allocation:

Uses simple mathematics to do capacity planning. Works only on containers & Datastores Reduces the CPU, VM or DISK SPACE allocated to a VM from the total available. The total available can be hypothetically increased by using Over commitment Ratios

CPU Demand: Amount of CPU resources an object would have used if there was no contention Demand (Mhz) for CPU comes from vCenter Metrics. Derived as Percentage by vROps Demand can be Greater than , Equal to or Less than Usage

Memory Demand: Derived by vROps by using Active Memory + Overheads

Network Demand: Derived by vROps using network usage per vNic as a percentage of the bandwidth.

Disk Demand: Sum of the queued IO commands and the outstanding IO commands as a percentage of the overall capacity. It is derived by vROps.

Why Using Demand instead of Allocation??

In Capacity planning in vRealize Operations,

• If you adopt an Allocation Policy, the Capacity planning engine will assume the resources you have allocated an Object are consumed.  So, if you have given a VM 2x vCPUs, 2GB RAM and 20GB storage, and those resources are consumed from your pool of resources from a Capacity reporting point of view.

If you adopt a Demand Policy, the Capacity planning engine will only consider the resources that are actually being used, or demanded, are consumed.  So if your 2x vCPU, 2GB RAM, 20GB disk VM is only actually using 0.5 vCPU, 1,2GB RAM and 4GB disk the remaining resources are reported as being capacity still available.

To start the configurations we will start with the Following:

• Click on Administration, Click on Policies, Click on the Policy Library Tab
• Expand Base Settings to see all the policies
• Click on 'vSphere Solution's Default Policy (**/**/**)’ Click on the Pencil icon to edit the policy

When you edit a Policy you will be taken straight to the Override Analysis Settings Panel. This is where you can change the capacity model for each Object type. We need to change the CPU and Disk models from an Allocation policy to a Demand policy.

Change the Settings for CLUSTER COMPUTE RESOURCE Object type:

1. The list on the left, contains the Object Types you can change policy for and you can use the selectors to add Object Types to the right hand panel as needed. For this lab, we have already added the required Object Types to the workspace.
2. Each Object Type has its own section with Policy Elements.
3. Use the arrow to open or collapse the Object Type - the first Object Type will, by default, be opened up.
4. Where a Policy Element is greyed out it means no changes to the Base (default) Settings have been made to it. If you wanted to make a change, simply slide the switch to the right.
5. Where the switch has already been opened and you see a tick, changes have been made to the Base (default) Setting. The first Policy Element you will see with changes is Capacity Remaining. We need to make further changes so:
6. Click on the Arrow to expand the Capacity Remaining policy element.

1. Scroll down a bit so you can see the entire Policy Element section.
2. Click on the arrow to expand the CPU section
3. Uncheck the Allocation box. This changes the policy on the Cluster Compute resource type such that we want the CPU dimension to only be measured on Demand.

We will do the same with Disk Space, Uncheck the Allocation box

Change the Settings for DATACENTER Object type:

Scroll down to the next object type, Datacenter, Click on the arrow to expand the policy elements.

Scroll down to the Capacity Remaining policy element and click on the arrow to expand it,

Expand the CPU resource container Uncheck the Allocation setting Scroll down, locate the Disk Space resource container and uncheck its Allocation setting

Change the Settings for (Host System, Datastore and vCenter Server) Object Type:

Scroll down to the Object Type Expand the Policy Elements for the Object Type Scroll down and expand the Capacity Remaining policy element Uncheck the CPU and Disk Space resource container Allocation settings as required you need to do the above for Object Types:

• Datastore - uncheck Disk Space only
• Host System - uncheck CPU and Disk Space
• vCenter Server - change CPU to Demand from Allocation and uncheck Disk Space allocation.

Enable The Hardening Guidelines Alert:

Click on the Plus to open 5. Override Alert/Symptom Definitions

Type Hardening in the filter field and hit Return.

Click on the Dropdown arrow next to Local then click again to see the dropdown. Select the ticked version of Local to enable the Alert Definition.

The Same for the Virtual Machine Alert

Click Save