Is this in a nutshell how the networking in vSphere works? Virtual vs physical picture examples.

[juntaos]

Hi!

I'm getting my head into the world of VMware networking. I've been looking around a little bit in our environment we got, and though I could ask here if I'm on track somewhat.

I've attached two files: one in a snip from a configuration of an ESXi host, and the other one is a Visio drawing that should be a replica of the virtual network, but in a physical manner. The reason for this is that I think it's easier for me, to get an understand by drawing in up physically.

The platform we are running ESXi on is Cisco UCS, and there is also virtualization going on there, so in this case the "physical adapters" isn't really physical, but that isn't so relevant for this example.

So if you please could compare these two attachments, I would really be grateful. Also got some questions on this:

Question 1:

Is it a fair assumption to compare a "Port Group" to like say a set of port on a switch that is assigned to a specific VLAN? I guess you use Port Group just for the fact that you can assign them to VLANs. Otherwise all the virtual machines would be in the same VLAN, if you don't create additional switches i vSphere and separate them that way?

Question 2:

I've been watching some online training videos, and seen that a lot of people creates many virtual switches. Why don't you just like have one switch? I mean the switch can dynamically increase ports (to how many?), and if you can just make more Port Groups, why would you want to create more switches?

Question 3:

If you want to use vMotion, must a VMkernel Port then be used?

Question 4:

Not really related to this, but I created a thread recently: A couple of questions regarding VMware vSphere and the issue I have is that I can't reply to it. There is no "Answer" button anywhere, but on other threads I can answer just fine. Anyone know why this is? So if I don't answer on this thread I probably got the same issue.

Also, if you got any additional resources that could help a newbie on the way, that would be greatly appreciated. Thanks you all so much for taking your time.

[a_p_]

Question 1:

Yes, that's correct. The main purpose for multiple port groups is actually separating VLANs. However, there may be other reasons too, e.g. using diggerent policies (failover, ...).

Question 2:

Separate vSwitches may be required if your physical infrastructure requires it, e.g. when using physical dedicated DMZ switches, ...

The maximum number of ports for different types of vSwitches, and totals per host can be found at https://www.vmware.com/pdf/vsphere6/r65/vsphere-65-configuration-maximums.pdf‌ (see Networking Maximums)

Question 3:

Yes, VMKernel ports are ports for ESXi host networking, i.e. features like Management, vMotion, Fault Tolerance, ... which run on the host rather than in the VMs.

Question 4:

I can see the Reply link at the right bottom of each post.

Regarding the screenshots: You do have a "VLAN 1" port group. Please remember that the physical port's native/default VLAN must not be tagged at the port group level, since this is already done on the physical switch port.

André