VMware vSphere 6.5 Deploying VMs and Hosts

to automatically deploy new ESXi hosts. So the purpose of Auto Deploy is to allow you to plug in a Bare-Metal ESXi host and have an ESXi image and a configuration automatically installed on that ESXi host. So let’s take a look at how it works. The first component that you need to set up And the PXE boot file is basically just enough information for this ESXi host to boot up and to issue an HTTP request to the Auto Deploy server. And so now the ESXi host will issue that HTTP request to the Auto Deploy server, which is actually just your vCenter server. And it will request an image. And depending on the rules engine of Auto Deploy, a certain image will be deployed to this ESXi host. So rules can be assigned to send different images to different hosts based on their MAC address, based on the vendor of the host, based on a fixed DHCP IP address. So we can set up rules to send certain images to certain hosts. And the rules engine is the part of the Auto Deploy server that makes those decisions. So when this image request hits the Auto Deploy Server, it’ll analyze its rules engine to figure out which image profile it should give to this Bare-Metal ESXi host, and then it’ll go ahead and deploy the image to the host. And now the image can successfully boot up as an ESXi host. So now we’ve taken a Bare-Metal host. It booted up, it did a DHCP request, it got the address of the TFTP server as part of that DHCP string. It got a PXE boot image from TFTP, reached out to Auto Deploy and it got a full ESXi image. And now we’ve completely imaged this ESXi host. And so the next step in this process is going to be to actually apply a configuration to the ESXi host. So as part of Auto Deploy, this ESXi host is getting added to a vCenter inventory. So when the Auto Deploy process finishes, this host is already going to be manageable by our vCenter server. And so now a host profile can be used to apply a standardized configuration to this ESXi host. And so now the host profile is used to apply that config and to get that ESXi host all ready to go. And now not only have we imaged it, but we’ve given a complete configuration according to our standard config with host profiles. So, what is this image made up of? Auto Deploy is going to install images on these ESXi hosts as they boot. What is the image made up of? It’s made up of a set of VIBs, or VMware Infrastructure Bundles, and every image profile includes a base VIB. That’s ESXi itself. So we always have that base VIB. But then we can have other VIBs added, like partner solutions and drivers on top of that base VIB. So you can actually create your own image profiles if you’d like to, using Image Builder. But many vendors provide their own pre-packaged images with all the correct drivers and add-on software that you may need for our particular model of the ESXi host. So most of the time, you can utilize a pre-packaged image from your vendor without having to actually build an image yourself. But if you do choose to build your own image, there’s a tool built into Auto Deploy for that called Image Builder. So here I am at docs.vmware.com again, and I’m looking at the vSphere six dot five documentation on Image Builder. And I just want to take you on a quick tour of the documentation here, and give you a rough idea of what to expect with Image Builder. Now, Image Builder is a command line tool. You can see here you’re going to have to install PowerCLI and all prerequisite software. And so that’s really step one, they start booting up an ESXi host. The host comes up, successfully boots with that image, and then there are a bunch of host profile settings that are actually noncompliant. So, the host profile can’t do absolutely everything. There are certain things about hosts that you may need to manually configure. Like for example, every host can’t have the same IP address. There might be also storage settings and things like that that you need to manually override. So you can check compliance with your storage policy. And then you can just go ahead and fill in the blanks. Whatever that storage policy needed, whatever it was missing, whatever is noncompliant, you can fill in those blanks for that host and bring that host into compliance with the storage policy. And then the final step they’re showing you here is doing a storage re-scan, and we’ve got a host that is now compliant with our host profile. And that’s really the entire process. So this is a great document because it not only gives you all of the steps for Auto Deploy itself, but it also walks you through a lot of these prerequisite steps and what they mean as well. So it’s a really high quality walkthrough of the Auto Deploy installation setup process, and how the hosts actually boot and get those images. Okay, so there are a few other options that you need to be aware of when it comes to Auto Deploy. We can do either Stateless, Stateless Caching, or Stateful Installs with Auto Deploy. And these are going to impact how you do things like upgrades. So Auto Deploy is a great way to easily upgrade your ESXi hosts. So let’s think about first a Stateless. So here’s a Bare-Metal ESXi host. It has no local physical storage at all. It’s got memory, but it doesn’t have any physical storage. And so as this ESXi host boots, it does its DHCP request. It gets its PXE boot image from TFTP, it reaches out to Auto Deploy, and the Auto Deploy rules engine determines the appropriate image for this ESXi host, and deploys that image to the host. And the image goes into memory. There is no persistent storage of that image anywhere. So what I mean by that is if I now reboot this ESXi host, that image is gone, and it’s going to reach out to Auto Deploy again, upon reboot, ask what image, the rules engine will be used to determine the correct image, and that image will be deployed to the host. So, if my hosts are on six dot O, let’s say they’re on ESXi six O, and I want to bring them up to six five, I can just change my rules engine, reboot those ESXi hosts, and they’ll all get a new image from the Auto Deploy server. So that’s the Stateless mode of Auto Deploy. Let’s take a look at another mode called Stateless Caching. So in this case, the ESXi host does have some sort of local storage. It’s got a little bit of local capacity. So when this ESXi host boots, it’s going to get a DHCP IP address, it’s going to get a PXE boot image, it’s going to reach out to Auto Deploy, and based on the rules engine, it’s going to get a particular image. And that image is going to be persistently stored locally on that ESXi host. So that’s Stateless Caching. Now what difference does that really make? Well, let’s say that for some reason the Auto Deploy server is unavailable. So if the Auto Deploy server itself goes down, and I try to reboot this ESXi host, it’s got a local copy of that image it can use as a backup. So that means that this ESXi host can boot up even without the Auto Deploy server. And if we think about our Stateless example, where it just put the image in memory, if I reboot that host and Auto Deploy isn’t around, that host is not going to successfully boot. So Stateless Caching keeps a copy of the image on local storage. But Stateless Caching, the primary option, when the host boots, it’s always going to try to pull an image from the Auto Deploy server, right? So plan A is to try and pull an image from the Auto Deploy server. If it’s down, then and only then will it boot from the local image. So the local image is strictly a backup when it comes to Stateless Caching. When it comes to Stateful Install, again, the host has local storage. It boots, gets an image from Auto Deploy, and that’s the image that it uses from that moment forward. And so a Stateful Install is a little bit different because it’s going to get an image once from Auto Deploy, and that’s it. If I reboot this host, it doesn’t reach out to Auto Deploy again. So this is a great way to get a new host imaged, and to locally install the image on that host. But it doesn’t really help so much with things like upgrades. If I want to upgrade from ESXi six to six five, or from six five to six seven, the Stateful Install option isn’t going to really help me do that. Because the ESXi host is always just going to use that image that’s on local storage.


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