Understand the basic configuration of a ESXi 6.5 vSwitch and VMkernel interface.
- [Instructor] VSphere networking consists of two major components, VMkernal networking and virtual machine networking. Both use virtual switches to manage configuration and connection information. A virtual switch provides us with a representation of how the VMkernal is going to pass traffic as it exits a virtual machine out to the physical network or to another virtual machine. All of this is configured through vSwitches. Currently we have vSwitch0 that was created during installation. And we can see from the graphical representation here, on the right hand side we have our physical adapters.
Those are our uplinks that are plugged into our physical switches, and on the left hand side we have our port groups. The port groups determine which virtual machines or VMkernal interfaces are all going to have the same configuration. Under the Physical Adapters I can click on the I to get some information about that physical adapter. It shows what type of NIC it is, what driver it's using, and then its current status information, as well as any network information about what it's connected to. That's based off of observed incoming traffic and it's not necessarily reliable, but it does give us a good indication of what networks that particular interface is seeing.
If we were connect to a physical switch that supports either CDP or LLDP, we would see information here from the discovery protocol, which would tell us more information about our connected partner, what port we're plugged into, what VLAN it's configured for, and things like that. On the left hand side we can also click on the little I here to get information about this port group. The first thing that I can configure is the default settings for the vSwitch. To do that, I select the vSwitch and then I click on the little plus above it.
From here I have four different categories where I can modify the configuration. The first one is Properties. In here I can change the MTU. The default MTU is 1500, which is the standard for Ethernet, and I can increase this all the way up to 9000. Keep in mind, however, if you increase this to 9000, then all of your physical devices also have to be configured to support jumbo frames. Our second option is Security, and this is going to determine how our virtual machines are allowed to communicate. First option under here is Promiscuous mode, and the default for that is Reject.
Promiscuous mode means that a virtual machine can receive traffic even if it's not intended for its MAC address. By default, a switch is not going to pass traffic to a virtual machine unless it's intended for its MAC address. If we set that to accept, then that virtual machine, or any virtual machine plugged into this port group or vSwitch, is going to monitor traffic even when it has a different destination. The default there is Reject and that's generally where you want to leave it. The next two options, MAC address changes and Forged transmits.
The default here is Accept for both of them. MAC address changes means do we want to allow for the virtual machine to report that it wants to receive traffic for a different MAC address? And Forget transmits means do we want to allow a virtual machine to transmit traffic from a different MAC address than its hard-coded address? All three of these need to be set to Accept for any network where we're creating ESXi hosts. Because they do need to receive traffic that is intended for MAC addresses other than their own, and they're also going to need to forge transmits as well as report MAC address changes.
We did that earlier for the physical cluster port group. Third option under here is Traffic shaping. This allows for us to control the amount of traffic that our virtual machine is allowed to transmit. We can set this to Enabled, and then we can configure the average peak and the burst size. It's very, very rarely used, so we'll leave it as Disabled. And our fourth option here is Teaming and failover. First option here is Load balancing.
This is going to determine how our virtual machines are bound to our uplinks. The default is Route based on originating virtual port and for the most part that's where we'll want to leave it. Second option here is Network failure detection. There's two options, Link status only and Beacon probing. Once again, in almost all cases we're going to want to leave this as Link status only. Notify switches indicates that when a virtual machine moves, either as a result of a vMotion or the failure of a physical NIC, we want to send a gratuitous ARP up to the physical switches to notify them that the MAC address changed.
Once again, in almost all cases we're going to want to leave that set to Yes. The one place where you might want to change that is if you're using Microsoft Network Load Balancing. Fourth option at the top is Failback. This is going to determine if a physical adapter fails and then later comes back, do we want to fail the virtual machines back to it? The default is Yes and more than likely we want to leave it there. Finally we have the option of changing the Failover order. The first category here is Active adapters. Any adapters that are listed under Active are going to be load balanced based off of the load balancing algorithm that I have configured.
Any adapters that are listed under Standby are only going to become active if one of the active adapter fails. Then finally any adapters listed under Unused are never going to be used for this particular port group. I can click on an adapter and then I can use the arrows to move it up and down through the list. Each VMkernal adapter plugged into a standard switch is going to have its own port group. And if I edit settings on that, I can change the same settings. If I want to edit the IP address of that VMkernal port, I need to go down VMkernal adapters and I can select it here.
For a more detailed discussion of networking with vSphere, see my Configure and Manage VMware and vSphere 6 Networking course. Now I'm going to make some changes to our lab network environment.
- Virtual machine benefits
- Building a lab environment with a mini PC
- Working with ESXi and vCenter Server
- Installing a control center VM
- Using the HTML5 client and the web client
- Adding an ESXi host and use Remote Console
- Configuring vSAN and storage profiles
- Adding NFS datastore
- Deploying a virtual machine from OVA
- Performing a cloning operation
- Using templates
- Performing a vMotion migration
- Working with snapshots