I recently encountered an interesting question, maybe not the one you will see every day. A vCenter Center server runs a large number of Clusters; the VMs on those clusters are controlled by a considerable number of DRS rules. The question that raised; “How do we know if the DRS rules we once designed are still in place?” In the course of time, rules can be disabled, VM or Host groups does not match any more. Trying to answer this question by going through the vCenter Server configuration is not the way to go.

Thankfully, the VMware PowerCLI contains a useful Cmdlet Get-DrsRule that enables you to create a dump of the configured rules for each cluster. This makes checking your configuration a lot easier.

But there is another thing, now we know about the configuration, but what do we know about the actual situation? For instance, VM to Host affinity has “should” and “must” rules, but to what extent is a “should” rule fulfilled?

So time to create a PowerShell script which performs the following tasks; for each Cluster within a vCenter Server, a dump of the configured DRS rule is made. The second part of the script determines on which host a VM is running and compares it to the configured rules. The script will also report if a DRS rule is disabled and displays the power state of each VM. You will probably worry less about a powered down VM.

The script can be found here on GitHub.

I am aware that the script and my programming skills are far from perfect, so expect updated versions in the future.

About update levels and build numbers (VMware)


You are working on a project, e.g. installing the latest VMware Horizon View on a vSphere 5.5 Platform. The VMware Product Interoperability Matrixes can help you determine which versions of ESXi are compatible with View.


This is not the best example, as this version of View runs on almost all version of ESXi, you might see the issue, as ESXi presents no update levels, just build numbers. So how do you match Update levels to Build numbers?

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My VCAP5-DCD Exam Experience


I am not the first and will definitely not be last to share an “Exam Experience” story, and normally I wouldn’t do so. So why would I bother you with this one? Well, because I think, this kind of exam is different from the usual IT related exams, like VMware VCP, Microsoft MCP, or Linux LPI exams.

First of all, some background why would someone go for this exam? I have a strong background in System Administration and System engineering and I passed my first VCP exam almost 10 years ago! The VCAP-DCA (Data Center Administration) exam is a good opportunity to test your skills in a live environment. So, I took that exam in 2012.

However, since a couple of years I am regularly involved in vSphere design projects. So it was time to build a solid foundation in the field of design. The following months, I worked my way through a lot of material. Working as a Designer is different from Administration and it is important to get used to a “Design Methodology”. Experience gained during the “administration years” is invaluable for building your in-depth technical knowledge, which is also needed.
The long-term goal was to test my knowledge by taking the VCAP5-DCD exam. The VMware MyLearn portal provides useful information for your preparations, like blueprints, recommended courses and other training material.

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