I am at VMworld 2010 Copenhagen this week and have noticed through informal customer surveys and conversations that the use of the Distributed Switch is low when compared to other vSphere features. This fact confirms what I discovered at the VMworld 2010 show in SF a few weeks back and in other more formal surveys I have seen of our customer base.
Why is this the case? One idea I have is that users don't really get the value proposition of the Distributed Switch. I discussed 2 of these areas (less setup, vMotion info capture from a network perspective) in a blog post last year. In addition to those benefits, I believe the need for just one port group brings up huge OpEx savings. Another element that is important to remember is that the loss of vCenter itself will not cripple the function of the switch. Some users believe this could cripple the environment but that is not the case. You can read more about that in an article I found on-line recently.
Distributed Switch also delivers traffic shaping and Private VLAN support.
Finally, the use of the Distributed Switch with vSphere 4.1 opens up the possibility of using the new Network I/O Control feature. Network flow types (of which there are six) can now be given equal priority for network resource access and then be given more advanced priority to say which flow gets the network resource in a congested environment. The graphic below shows this type of setup and also refers to the new load-based NIC teaming that can be used with NIOC to balance load across 2 10 GE NICS. NIOC becomes especially important in this type of environment.
My two questions to you are:
1. Do you use the Distributed Switch? If no, why not?
2. What do you think of the Distributed Switch in general?
-Mike