VMware VCA 1V0-701 – VCA-DBT – vSphere
In this video we’ll explore Vsphere six virtual machine concepts and the VMware certified associate exam is still focused on Vsphere six. So we’re not really going to get into any specifics when it comes to Vsphere six five in this or any other lesson in this course. So virtual machine is very similar to physical machine in many ways. A virtual machine has an operating system installed on it and that operating system needs access to CPU, to memory, network interface cards and storage. And the guest operating system of our virtual machine has no idea that it’s running within a VM. So the goal here is basically to trick the guest operating system into thinking that it has real hardware. So let’s assume in this scenario that our guest operating system is Windows. And we see in the little purple box here we’ve got a Windows virtual machine. Windows needs CPU and memory in order to execute so we’ll allocate a certain amount of those resources to this virtual machine. And Windows also needs a C drive for us to install the operating system on and space to store files.
So we will present virtual disks to it. And our virtual machine also needs to transmit traffic on the network. And in order to do that, Windows needs to see a network interface card. So we’ll install some network interface card drivers in Windows and present an adapter to the guest operating system. And as far as Windows or whatever guest operating system we happen to be using is as far as the guest OS is concerned, this virtual hardware seems exactly the same as physical hardware. Now one of the resources that we’re going to present to our virtual machines is CPU and memory. So let’s assume in this scenario our Windows virtual machine has been created with two virtual CPUs and has been allocated 8GB of memory. What that essentially means is that this virtual machine is going to be able to utilize the CPU resources of two physical processor cores or Pcpu physical CPUs.
That’s all we’re saying. So if we create a virtual machine with two virtual CPUs we’re not guaranteeing it full rain over those physical processors. There may be other virtual machines that it’s sharing those processors with. What we’re saying when we give a virtual machine two virtual CPUs is we’re saying you’re allowed to use two physical processor cores if they’re available. They might not be available. They might be used by other virtual machines. So we’re not making any guarantees here. And the same concept goes with memory. We may create a Windows VM and give it eight gigs of memory and that’s what Windows will see. Windows will see two processors and eight gigs of memory. But again, we’re not guaranteeing this VM eight gigs of memory. And by the way, the VM is only going to take up the physical memory that it actually needs. So if this particular VM is only using four gigs of memory at the moment, that’s all that it’ll take up on the ESXi host.
This is referred to as thin provisioning of memory and our virtual disks operate in a similar manner. Again, we’re going to trick our guest operating system. So just like memory and CPU, the virtual machine doesn’t really have any actual hardware. It’s accessing a shared resource. And in this case, that resource is called a data store. Windows needs to see storage hardware, so we’ll trick Windows into thinking it has a scuzzy controller. We’ll provide drivers for a virtual scuzzy controller. So when Windows needs to read and write data, it generates scuzzy commands. And those scuzzy commands are set to the virtual scuzzy controller, which is basically fake hardware. And when those scuzzy commands arrive at the virtual scuzzy controller, it’s the job of our ESXi host to redirect those commands towards the appropriate storage location. That’s how we achieve storage virtualization. And this is an important slide to understand because if you really understand this slide, you kind of get the whole concept of virtualization.
This is a virtual machine that believes it has disks, it believes it has memory, it believes it has CPU. The guest operating system doesn’t know that in reality, all of those resources are actually shared resources that are used by many other virtual machines. And that’s the whole point of what we see here with the hypervisor and the layer of abstraction. Decoupling those resources from the virtual machine gives us flexibility. It means that we can take this virtual machine’s files and move them to some other data store. And if we choose to do that now, what happens as a side effect is the virtual machine does not know the difference, right? Windows does not know the difference. If I take this virtual machine’s files and I put them on some other data store up here, then the next thing is next time a scuzzy command comes out, the hypervisor will be aware of that and will direct it towards the appropriate storage location. But as far as the VM can tell, nothing has changed. It’s still got its virtual scuzzy controller and that’s how the storage traffic is still getting from point A to point B.
So from Windows perspective, nothing changes even if I relocate the files that make up that virtual machine. So the whole objective here is to trick the guest operating system into thinking it has real hardware, when in reality it truly doesn’t. And giving us this layer of abstraction in the middle to allow us some managerial capabilities. And the concept is very similar with networking. So just like CPU and memory and storage, the VM doesn’t have any dedicated physical hardware. It’s going to access a shared resource. And in this case, the shared resource that’s going to be utilized is the physical adapters of the ESXi host. And here we see a virtual switch with some physical adapters. So when you have a bunch of VMs running on an ESXi host. That host might have some ethernet ports on it. That’s what these are, that’s what my physical adapters are. But this is still a Windows virtual machine. And if Windows is going to send traffic on the network, then Windows needs to see a network interface card.
So that’s part one of this equation is to fool Windows into thinking it’s got a physical network interface card. So we’ll present a virtual nic to this guest operating system and when the virtual machine sends traffic out to the network, the guest operating system is going to send that traffic to the virtual nick. And from there the traffic will flow out of the VM and be relayed to the virtual switch that this VM is associated with. And the virtual switch is actually assigned to Vmnext or physical adapters so that if necessary, that traffic can be switched out to the physical network to maybe some destination physical server or something along those lines. And then finally we can also connect USB devices, we can connect ISO images to our virtual machines. So we have a wide variety of different storage and other sorts of hardware that we can integrate with this VM.
Okay, so in review we learned that virtual machines are presented virtual hardware and the guest operating system is essentially being tricked by this virtual hardware. So the guest operating system has no idea that it’s actually running as a virtual machine. Virtual hardware version eleven was the current version with Vsphere six. We also learned a little bit about virtual disks. Now as we move throughout the course, we’ll dig a little bit deeper on how storage actually works and we’ll learn about the differences between thin and thick provision disks and we’ll have much more on that. If you ever take the Vsphere six foundations course that should be coming out shortly, we’ll have a lot more detailed information in there about virtual disk types.
And then finally a virtual nic is also provided to our virtual machines as well. There’s a specific type of virtual nic called the VMX net three that’s recommended in most cases. But regardless of the type of virtual nic that you use, the concept is still the same. We’re presenting a fake virtual network interface card to our voice.
In this video, I’ll explain the role of Vcenter, the Platform Services Controller, and how they are used to manage our ESXi hosts. So here we see a little diagram, and basically the point of this diagram is to illustrate that Vcenter is used to manage our entire Vsphere environment. So in the big green box here, that represents Vcenter, and then within it, I might have multiple virtual data centers that include ESXi hosts, virtual machines, data stores, virtual switches, and all of these different components that make up my virtual data center. But Vcenter is the top level of administration. I can use it to manage many ESXi hosts at once. And Vcenter also hosts My Vsphere web Client as well. So technically, we could actually manage individual ESXi hosts using the Vsfair client. But as the environment continues to grow, this starts to become really impractical.
So Vcenter gives us that central management system so that we can control everything at once from one unified Web client. And not only does Vcenter give us our central management capability, but it also makes certain features possible. You can’t do. V. Motion storage v. Motion high availability, fault tolerance DRS, storage DRS and many other features require Vcenter to be available. So Vcenter is not just a management platform, it unlocks a lot of capabilities that are not possible if we choose to not deploy Vcenter.
So we have a few different options of how we can actually create our Vcenter server. There’s the Vcenter Server appliance, or we can deploy Vcenter on a Windows machine. And the first option is to set up a Windows virtual machine and install Vcenter on it. So we can install Vcenter on top of any of the supported versions of Windows. This does require a Windows license, of course, and because it’s running on a virtual machine, we can protect Vcenter with either High Availability or Fault Tolerance. So we can give ourselves the ability to recover from a failure of an ESXi host. Now, we could also potentially deploy Vcenter on a physical server running Windows, and this gives us complete segmentation of management. We’ve got our management server running on a separate physical device, and this might be required for compliance purposes, but it’s usually not recommended because we can’t protect the physical server with High Availability or Fault Tolerance. So it doesn’t have the same level of redundancy that a virtual machine would give us.
Now, an option that’s becoming more and more popular is to configure a Vcenter Server appliance. And the Vcenter Server appliance is a pre built, preconfigured virtual appliance that’s designed to run Vcenter. Basically, you download it, you import it to run on an ESXi host, and you immediately have a complete Vcenter configuration that’s very easy to install, very easy to upgrade, and it’s a virtual machine that can be protected with High Availability or fault tolerance. And we don’t require a Windows license. So traditionally, the Windows V Center has been more popular because it had a higher set of features, it was compatible with additional databases, it could support more virtual machines, more ESXi hosts. But now we have feature parity between the two. So you may need to know a couple of things about the supported databases really quickly.
The Windows version of Vcenter supports Microsoft SQL, Oracle or a bundled database. The bundled database can be scaled up to a maximum of 20 hosts or 200 virtual machines. Whereas the Vcenter Server appliance does not support SQL, it supports Oracle and it also supports an embedded database. And that embedded database is just as scalable as any of these external databases are. So now the Vcenter Server appliance with an embedded database scales just as high as any of the other options do.
So for the purposes of the VMware certified Associate Exam, what you really need to know is, number one, that Vcenter provides our central management system for all of our ESXi hosts, all of our virtual machines, and all of our data stores. You also need to know that Vcenter is required for certain features like High Availability, fault tolerance, distributed Resource Scheduler, and you need to understand that it’s used in Van image are physical ESXi hosts. So those are the actual hosts. That my virtual machine.
In this video, I’m going to demonstrate the installation of the Client Integration Plugin. So you’ll notice here I have launched the website for my Vsphere webcam. And down at the bottom left, you’ll notice that we have this little link to download the Client Integration Plugin. And if I click on this link, what it’s going to do is it’s going to simply start downloading a file. So I’m going to go ahead and save this file to a folder location, my downloads folder. And you can see I’ve already downloaded this once a long time ago. I’m going to go ahead and replace that copy with a new copy of the Client Integration Plugin. What the Client Integration Plugin does is it allows certain features of the Vs for Web Client to work. For example, you’ll notice here if I’m going to log into the Vsphere web client, I can check this box to use my Windows Session authentication.
And what that means is if I’m already logged in to a Windows machine with credentials that can also be used for the Vsphere web client, I can simply pass those credentials through and I won’t have to authenticate again. Okay, so let’s take a look at my downloads folder here. And here you can see the VMware client integration plugin installer. I’m going to go ahead and launch it, and you’ll notice I’m going to have a problem during the installation because I’ve got Internet Explorer running in the background. So you cannot install the Client Integration Plug in while you’ve got one of your browsers up and running.
So I’m going to just go ahead and retry now that I’ve closed out Internet Explorer. And so what it’s giving me here is the option to remove or change or repair my installation because I’ve already got a preexisting installation of the VMware Client Integration Plugin installed. So I’m just going to leave my current installation of the Client Integration Plugin intact. I’m actually not going to change it at all. What I really wanted to show you in this demonstration is the fact that if you want to launch the Client Integration Plugin installer, you have to make sure you close out of Internet Explorer.
You can’t have any browser windows open. And I also want you to understand a couple critical things about the Client Integration Plugin. Number one, it allows you to pass through those Windows session credentials. And that means potentially you may only have to log in once, and you can just push through those credentials that you’ve already logged into Windows using. So now that we’ve successfully logged into the Visa Web client, let’s take a look at a couple of things that we can do using this Client Integration Plug in. I’m going to go to Hosts and Clusters, and there’s a couple of tasks that we need the Client Integration Plug in in order to perform. And one of those tasks is to deploy a virtual appliance. So let’s say for example, we have a pre built virtual machine that is deployed as an OVF template, and I now want to import that virtual machine into my V Center inventory. Well, I can do that by simply going to an ESXi host and right clicking it, and I can say I want to deploy an OVF template, and I can browse to a location on my computer where that OVF template is installed. Well, it won’t allow me to do this unless I have the client integration plugin installed. And so here it’s telling me I can either download the client integration plug in and go ahead and install it.
Now, if you’ve already installed the client integration plug in and you’re getting this prompt, my recommendation is to go ahead and launch the Client integration plugin installation and completely remove whatever you currently have installed. You want to completely remove any remnants of the client integration plug in and reinstall it from scratch. So now that I’ve explained the basics of the client integration plug in, one last final item that you may want to be aware of for the VMware certified associate exam is we need that client Integration plug in to also go ahead and launch a remote console for this virtual machine. So, at the moment, I am unable to actually open a console to this virtual machine. If I get the client integration plugin installed and functioning properly, that will no longer be an issue.
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