Tag Archive | vmware

The Great vSwitch Debate – Part 2

Table of Contents

Part 2

This article is a continuation of the first in a series. See The Great vSwitch Debate – Part 1 for the beginning of the series.

In this Part Two of the series on vSwitch configurations, I want to address some of the advanced configuration options, but first – I need to go back and revisit the end of Part 1. There, I was discussing the routing of traffic between VMs on the same and different port groups on a single vSwitch. I presented the figure below (Figure 1) to describe what I was talking about.

Figure 1. Port Group Communications Paths

Figure 1. Port Group Communications Paths

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The Great vSwitch Debate – Part 1

Table of Contents

Part 1

There are many articles out discussing “best practices” for configuring virtual switches (vSwitches) in a VMware Infrastructure 3 (VI3) environment – well, here’s the first in a series of articles that present vSwitch recommendations that conform to the rules of “Virtualization According to Ken”.

For purposes of clarity, unless otherwise specified, all discussion herein applies to both VMware ESX Server (ESX) and VMware ESXi Server (ESXi). When I want to make it clear that I’m referencing both, I’ll use the construct ESX/i.

First, let’s start out by defining exactly what a VMware vSwitch is: Read More…

When is it OK to default on your VI?

I’ve noticed something about engineers. They’re never happy with the way something is configured out of the box – there’s always a better way! Well, I have a different philosophy:

“If you don’t have a very good reason to change a default value, don’t change it!”

To me, this seems totally obvious – in most cases, the default values are there for a reason.

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Reaction to “Say it isn’t so: Hyper-V and XenServer outperform ESX”

Jason Boche posted an interesting article on his blog today, and I thought I’d offer my thoughts on it.

First, here’s the article from Virtualization Review magazine that started all this furor!

My guess is that part of the difference comes from both Hyper-V & Xen requiring VT capable CPUs (i.e. the VM always runs within a VT jail) while ESX supports binary translation (BT) for some 32-bit x86 instructions. The first generation of chips that supported VT weren’t very good, and VMware’s BT would often do a better job of executing the protected instructions than the hardware assist provided by the CPU. Intel has gotten better in the hardware support for virtualization which is shown in the subject test.

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