Today a basic example of super metrics; a special type of metric that’s available in vRealize Operations (vRops). vRops, VMware’s operations management solution, is designed to collect large numbers of objects and metrics in the vRops database and do some advanced analysis on these objects and metrics.
Objects are items that are monitored in your environment, such as virtual machines, clusters, hosts en datastores. Metrics are counters that are collected for these objects, for example CPU usage, RAM usage or free capacity on a datastore.
A super metric is special kind of metric, that provides a value based on other metrics. So in case a specific (required) metric is not available in vRops, you can create it yourself using a super metric. Most of the time a super metric is calculated using a formula.
To demonstrate how super metrics work, I am using a simple dashboard that’s available on the website of Sunny Dua of vxpresss.blogspot.in. The dashboard is called the datastore utilization dashboard, and can be downloaded here (search for Datastore utilization dashboard). There are also some other nice dashboards available on this webpage.
Import the dashboard and wait for a couple of minutes. The dashboard will present an overview of available datastores and virtual machines, and includes information on the disk/datastore size in GB, used space in GB and free space in GB. If you want to, you can add the metric Capacity->Used space % and/or Guest File System stats->Total guest file system usage to get info on the % of used space on a datastore and/or guest file system:
But, what if you also want to add the counter free space %? This counter isn’t available, but you can create it yourself using super metrics.
Create a super metric
Go to content->super metrics, and click the plus sign to create a new super metric. The formula we’re going to use is 100 – Capacity->used space %. The result is the free space %. The super metric looks like this:
The “this” pointer will tell vRops that this super metric is applicable to the selected object and not the aggregation of all available objects of specific metric. In vRops you will see something like this:
Create a second super metric for the percentage of free space in a virtual machine:
No you have to tell vRops to which object the new metric is applicable. This is of course a datastore and a virtual machine. Close the previous screen and link the new super metric to the related object.
Add the super metric to the policy
Before we can actually use the metric, we have to add the super metric to the (active) policy for the objects we want to monitor. Open the active policy, look for the newly created metrics and activate them in the policy:
Now wait for a couple of minutes, vRops will execute some actions in the background and the super metric will show up in your list and can be used in your dashboards.
In the last step you can add the new metrics to the dashboard, presenting information on free space as percentage:
I hope this was useful, you can leave your comment below!