As I build up my knowledge for the VCAP5-DCA one item that I realize I have no clue about is AutoDeploy. AutoDeploy basically has a couple of prerequisites; one being Image Builder, which we have already covered and the second is Host Profiles. Auto Deploy uses Host Profiles in order to configure the host once it has loaded it's image. Configuring things like datastores, networking, etc..
First, we need to create a Host Profile. Browse to your Host Profiles view in vCenter and select the 'Create Profile' button. There are a couple of options for creating, you can either import one or create one from what will be called a reference host (A host that you have setup perfectly that you would like to duplicate). In this example we will create a profile from an existing host. The wizard is pretty simple, select a host and give your profile a name.
Now that the profile is created we can go and explore the settings inside it by selecting the profile and clicking 'Edit Profile' along the top bar. Within the Edit Profile screen there is a ton of information and this where the blueprints skills mostly reference to. One of the skills to to use Host Profiles to create sub profiles. As you can see there is already a number of sub-profiles in our main profile. For instance, the NFS sub profiles are shown below; the three 'NFS Storage configuration' options are actually mount points to certain NFS datastores that will be deployed with the profile. If we wanted to add another we could simply right-click on the NFS storage configuration folder and select 'Add Profile' and then fill in the required information for another NFS mount.
The blueprint also mentions deploying vSphere Distributed Switches with host profiles. This is something that I have never done so I will try and fumble through it here 🙂 There is a great whitepaper which outlines the process as well here. First off, I've already done most the work as I had a vDS already setup on my reference host when I created the profile from it. If you didn't, you would need to go back to that reference host, create the vDS, attach the host and the re-create your Host Profile from it. From there it simply just looks as if you need to attach the profile to a host and provide some answeres around the networking and IP information, however, in the case of AutoDeploy we would probably want to use an answer file which we will discuss a bit later.
The blueprint also mentions storage configuration settings within Host Profiles as well so it's best to go over some of these. Aside from the NFS scenarios I mentioned earlier you may want to have a look at some of the below sub profiles
Native Multipathing -> SATP default PSP configuration – this is used to define a default path selection policy for a given SATP. A very real world scenario – you may want to set your EVA up to default to Round Robin, etc…
Pluggable Storage Architecture -> PSA Claimrule – Remember a week or so ago when we discussed creating claim rules for LUN Masking, well, these are in Host Profiles as well in the case you need to apply a claim rule to multiple hosts.
iSCSI Intiator Configuration – Software iSCSI Initiator – explore around in here as this too is a real-world scenario. You may want to prepopulate your discovery IP address, ensure the software initator is always vmhba##, CHAP settings, etc…
Attaching, checking for compliance and applying host profiles is pretty simple and can be done by right clicking a host and naviging through the Host Profile context menus. You will see when you apply a profile the host needs to be in maintenance mode and a lot of the time you will be prompted for input in regards to passwords, IP addresses, etc…To get around having to enter this input that is unique to a host (and for use with AutoDeploy) we can generate answer files.
Answer files are managed through the Hosts and Clusters tab in the Host Profile settings in vCenter. As you can see below I have a couple of hosts that have an answer file status of unknown – meaning it has no idea about the answer file.
In order to update these answer files it's as simple as right clicking on the host and selecting 'Update Answer File'. From there you will be prompted to enter in all of the information that requires user input such as IP Addresses, etc…
That's really it for Host Profiles. I don't expect the exam to quiz you on every possible sub process as there is a lot of them but the blueprint does specifically call out vSphere Distributed Switches and the storage configuration sections, so I would definitely have a poke around the lab in those two sections. The security section may also be a good one to explore as I tend to use it the most when dealing with Host Profiles.
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