I receive the same question around dvSwitches almost every week; should I only use dvSwitches or go for a hybrid model? The whitepaper that has been released a couple of months ago clearly states that a hybrid model is a supported configuration but would I recommend it? Or would a pure vDS model make more senses?
Let me first start with the most obvious answer: it depends. Let’s break it down and create two categories:
- Hosts with two NIC ports
- Hosts with more than two NIC ports
Now most of you would probably say who the hell would only have two NIC ports? Think 10Gbe in blade environments for instance. With only two physical NIC ports available you would not have many options. You would have exactly two options(if not using Flex-10 of course):
- Pure vDS
- Pure vSwitch
Indeed, no hybrid option as you would still want to have full redundancy which means you will need at least 2 physical ports for any virtual switch. Now what would I recommend when there are only two physical NIC ports available; I guess it depends on the customer. There are multiple pros and cons for both models but I will pick the most obvious and relevant two for now:
- PRO vDS: Operational benefits. Updating port groups, consistency and increased flexibility with vDS.
- CON vDS: If vCenter fails there’s no way to manage your vDS
There it is; probably the most important argument on why or why not to run your Service Console on a vDS. If vCenter fails there’s no way to manage your vDS. For me personally this is the main reason why I would most like not recommend running your Service Console/VMkernel portgroups on a dvSwitch. In other words: Hybrid is the way to go…
I guess it all comes down to what you are comfortable with and a proper operational procedure! But why? Why not just stick to Hybrid? I guess you could, but than again why not benefit from what dvSwitches have to offer? Especially in a converged network environment being able to use dvSwitches will make your life a bit easier from an operational perspective. On top of that you will have that great dvSwitch only Load Based Teaming to your disposal, load balancing without the need to resort to IP-Hash. I guess my conclusion is: Go Distributed… There is no need to be afraid if you understand the impact and risks and mitigate these with solid operational procedures.