I updated the diagram (v1.2) to fix a small typo and adjust also a couple of shapes. Thanks to Joshua Liebster & Bert Bouwhuis for driving my attention to this.
I know everybody skips to the diagram so I’ll save you the introduction, just make sure to quickly go through the notes that follow it:
- This is not an introduction to the VMware HA, and it’s not a very advanced diagram for it either. I assume here that you have a general idea on the topic before looking into it to appreciate this incredible technology. If you are a VMware professional you may also find this useful to keep your information sharp and present about the topic at any given time. You really don’t have to re-read the documentation every time you’d like to remember a small detail about the subject.
- I’m introducing in this diagram the “Layers” feature in Visio for the first time. The diagram may look somewhat confusing at the first glance, so I thought that it might be a good idea to use these layers for you to hide/show the topics that you are going through in the diagram. I can see some other use cases for the Layers in future diagrams, so I hope you will like it.
- This is an A3 diagram, sorry I know most of you just love the traditional A4 from the feedback I get, but seriously, it’s just TMI to fit in A4.
- Everything you see in this diagram, and specifically for the admission control, is *not* fictitious. This is a real cluster I built specifically before designing this diagram. I wanted everything to be 100% accurate and more importantly: realistic. If you zoom into the middle of the vCenter shape, you will be able to see the actual screenshot of the vCenter interface showing the HA cluster I used, and its runtime information window as well.
- It’s worth mentioning that this is not all the “advanced options” that you can use for VMware HA. I just selected the ones I thought that might be more frequently used. You can always get back to the official VMware documentation for the complete list.
- The Admission Control was probably the hardest part not just to visualize it, but also to understand it in the first place! That being said, I do not expect anyone with no prior reading on this specific topic to just get it from the first glance when he/she looks into the diagram. Duncan Epping has an excellent article that I think everyone already knows about it, but it’s worth mentioning that it’s the best place you will ever find for VMware HA in general. The diagram should help you though to understand it faster and easier. You can see all the numbers/calculations in front of you in one shot, and how all these numbers are related to each other.
- This HA lab was built in nearly 5 minuets and is 100% virtual. Long live Lab Manager 4.0 ! (more details here)
That’s all folks! I hope you will find it useful!