Migrating virtual machines using PowerCLI

In my current role as a VMware architect, I architected a greenfield VMware vSphere 6.5 environment.
The ‘old’ environment, who I architected 4 year ago, is VMware vSphere 5.5. As the old environment was never updated, the time and risk of upgrading this environment was too high. That’s why, we decided to go for a greenfield installation.
As the new environment was accepted by the customer system administrators, we had to migrate 700 virtual machines to the new environment.
The old environment was using NFS datastores, as the new environment is using hyperconverged.
As the old environment was vSphere 5.5 U1, we weren’t able to vMotion virtual machines to the new cluster, using Cross vCenter vMotion.

To make the migration as painless as possible, I create a PowerCLI script to do the hard work for us.

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VCSA CLI install error: format requires a mapping

While writing a standard vCenter installation procedure for a customer, I was testing the CLI installation of the Platform Service Controller (PSC) for VMware vCenter 6.5.

I really love the CLI installation method, it enables you to perform the same install procedure over and over again. If you want to know how to create a CLI install for the VCSA, I wrote a blog post about this topic a while ago.

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This week, I had the opportunity to speak at the Dutch VMUG (NLVMUG) about a project I did last year.

Title of my session was: Migrate your datacenter without downtime

Session abstract
Moving a complete datacenter 50 KM, without downtime?
A few years ago this was unthinkable, but with the help of VMware techniques this is possible nowadays. In this customer case, Michael Wilmsen shows you how he did this for a university, using VMware techniques and PowerCLI. Not only the process of script development, but you will also get a better understanding of how the VMware techniques work and how they are applicable.

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Testdrive Infinio Accelerator 3.0

Nowadays, many legacy storage devices (SAN/NAS) have the option for hosting flash devices in their solution. Flash devices leverage high IOPS and low latency.
Most common used storage protocols (iSCSI, NFS and even Fiber Channel) are bandwidth optimized, and are not latency optimized. Of course Fiber Channel (FC) has a lower latency, as Ethernet based protocols like iSCSI and NFS. But still remote device will have a higher latency as local devices. In this blog post from Mellanox, they explain why FC is doomed according to them.

In the past I wrote a blog post explaining why you want your flash devices as close as possible to your applications. Hence why Hyper Converged Infrastructure (HCI) are so popular nowadays.

But what if you have a legacy storage solution, and still want low latency for your applications?

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VMworld 2017 US Recap

This year, I was rewarded with a blogger pass for VMworld.

In this blogpost I want to highlight, what was striking to me.

Solutions exchange

Every year I like to walk around the Solution Exchange, talking with vendors and learning about their solutions.
What was surprising to me this year, was the size and the quality of boots. Comparing to other VMworld, the boots where much larger and had more lighting and some of the even LED screens. I know that the development and a spot on the Solution Exchange is not cheap, so clearly these vendors see the importance of being present and want to invest in an event like VMworld.


I’ve attended a couple of sessions, as most session are recorded and can be watched online after VMworld. The sessions I’ve attended, these sessions were striking to me.
Most of these session will also be in VMworld Barcelona.

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