Join Rick Crisci for an in-depth discussion in this video Virtual switch features, part of VMware vSphere 6.5 Essential Training Part 1.
- [Instructor] In this video we'll learn about some of the features that can be provided with vSphere Standard and vSphere Distributed virtual switches. Some of these features are unique to the Distributed switch only. So with vSphere there's two different types of virtual switches. The Standard virtual switch comes with all licensing additions and it has a basic feature set. Whereas the vSphere Distributed switch has an enhanced feature set and is only available with the Enterprise Plus licensing edition.
So I'll differentiate between the two as we go through all of these features and learn about them and the first feature that we're going to talk about here is discovery protocols, either CDP or LLDP. CDP stands for Cisco Discovery Protocol and LLDP stands for Link Layer Discovery Protocol. These are useful features that have been around for a long time on physical networking hardware.
What these discovery protocols are used for is to learn information about other network devices that are connected. Like for example, in our little diagram here assume that this ESXi host has a vSphere Standard switch. So if you got the vSphere Standard switch configured on the ESXi host and that vSphere Standard switch has some physical connections to a Cisco switch, a physical switch.
We can configure Cisco discovery protocol to allow it to discover some of the characteristics of the physical switch itself. We're gonna allow it to learn information about the physical switch. Things like the IP address of the switch, things like which physical adaptor is connected to which physical switch port. All right, so VM nick zero is connected to, you know, physical switch port zero one, VM nick one is connected to switch port zero slash two.
Right, and that can help us to make sure that we don't accidentally unplug the wrong cable. So that's CDP, Cisco Discovery Protocol and that is a Cisco specific discovery protocol that is available on a vSphere Standard switch. LLDP is basically the exact same thing except for it's not a Cisco specific technology. LLDP stands for Link Layer Discovery Protocol and it's only supported on the vSphere Distributed switch, but it does basically the exact same thing.
It just allows you to discover information about the other devices on the network. When we're using a vSphere Distributed switch we can create traffic marking and traffic filtering policies. So for example we could create a filtering policy for some incoming traffic from a certain IP address range or a certain TCP port and when that traffic hits the vSphere Distributed switch the vSphere Distributes switch will take the specified action, maybe dropping the packet.
We could even have it take certain actions like assigning class of service or DSCP tags to provide quality of service on outgoing traffic. So as this traffic is leaving the virtual switch and heading to the physical network we can setup a policy in the vSphere Distributed switch to create these class or service or quality of service tags and then as that traffic hits the physical network it will actually respect the quality of service values that we've appended.
So that's traffic filtering and tagging. It's basically an access list in the virtual switch that can drop or accept certain types of traffic or can apply quality of service values. Again, in this course we cover this at a very basic level. I just want you to be familiar with the features that are available. We don't really get into how to configure a lot of these features or a lot of the very detailed specifics about how these features operate. We just want you to be aware of the features that are available and what they do.
So another good feature is network health check. Again, this is something that's supported only on the vSphere Distributed switch and basically here is what network health check does. You can run a network health check in the vSphere web client and what it will do is it will compare the configuration of your vSphere Distributed switch, like really critical configuration items like what's the MTU or what's the NIC teaming method or the VLAN configuration. It'll compare those configurations to how the physical switch is configured and tell you if there are inconsistencies that you can easily identify and fix.
So that's the purpose of network health check is to validate the configuration of the vSphere Distributed switch against the configuration of a physical switch. NetFlow is another feature that's only supported on a vSphere Distributed switch. What it basically does is it tracks all of the traffic that's going on in your environment and it sends reports to a centralized server. It's kind of like a kid that tells on all his friends and the NetFlow connector is like the mom that he's telling on them with.
So for example let's say that, you know, we have a virtual machine that sends some traffic to an email server. Well what will happen with NetFlow is the virtual switch will actually track that traffic and it'll send a little report to this NetFlow collector saying hey, you know, 10.1.11 just talked to this email server over port 80 and here's how much traffic it's sending. This allows the NetFlow collector, whether it's like what's up gold or solar winds or any of those options.
It allows the NetFlow collector to build up a detailed historical record of all the traffic that's occurring on this network so that if you need to do forensic analysis or figure out, you know, traffic patterns over time or maybe you have an issue that occured at like one o'clock people said everything was slow. Well now you can go into that NetFlow collector and look at what was happening at one o'clock and you'll have a nice historical record of all of the traffic occurring.
That's the purpose of NetFlow. Again, this is something that's been around forever in the physical network, and the vSphere Distributed switch can be configured for NetFlow and can send these reports to a NetFlow collector. The last feature we're going to talk about here is port mirroring. So port mirroring can be used to send a copy of all the traffic on one port to another port. So for example let's say that this traffic is flowing in and it's destined for one of these virtual machines.
Well we can setup a port mirroring session to say any traffic for this particular port should also be mirrored to this other port. So maybe what I want to do is put a sniffer or put, you know, Wireshark or something running on this second port so that I can monitor all the traffic that's actually hitting the first port. That's what port mirroring is used for and there's all sorts of different port mirroring session types that you can setup.
Again, we do more in the other vSphere courses, we kinda get a little deeper on those things for the purposes of the VM or certified associate. What you need to know is port mirroring is a way to take all of the traffic that's occurring on one port and send an identical copy of that traffic to some destination, usually another port on a Distributed switch. Okay, so let's take a moment to review. In this lesson we learned about Cisco Discovery Protocol and Link Layer Discovery Protocol and how they can be used to discover information about other network devices.
We learned about NetFlow and how it can be use to send historical traffic records to a centralized collector so that we can analyze historical traffic patterns and do things like forensic analysis or determine the root cause of intermittent performance issues. We learned how traffic filtering and marking can be used on the vSphere Distributed switch to do things like drop certain types of traffic or apply quality of service tags to certain types of traffic and we learned how port mirroring can be used to take traffic that's occurring on one port and send a mirrored copy of it to another port.
- vSphere editions
- Installing and configuring ESXi
- Virtual networking with vSphere
- Working with distributed and standard switches
- Virtual storage
- Creating NFS data stores
- iSCSI storage
- Creating virtual machines and vApps
- Duplicating machines with templates and cloning