vSphere Host Profiles: Using Customization Files

Overview

If you own vSphere Enterprise Plus licences, using vSphere Host Profiles is a no brainer. Even if you rarely add ESXi hosts to your cluster, why configure them by hand if you can do that by a few mouse clicks in a fast and consistent manner.

Host profiles are usually created by setting up one ESXi host according to your requirements and then capturing its state. Some settings in a host profile are unique to each host, which include the host name, VMkernel adapter network settings, user name for joining host to AD, etc. When you apply your profile to a new unprepared host, vCenter will ask you to specify these settings. This step is called host customization.

You can either type these settings manually or if you want to take your automation game one step further, you can use a customization file, which is simply the list of setting in .csv format.

This feature was first introduced in vSphere 6.5 and official documentation is a bit light on this topic. Purpose of this post is to close this gap by demonstrating where to find this configuration option.

Create

To create a customization file, right click on a ESXi host and choose Host Profiles > Export Host Customizations. This host has to have host profile already applied to it (including all customization settings), otherwise this option will be grayed out. This can be the first host you used to capture the original host profile.

Open .csv file in your editor of choice and change settings accordingly. If you adding multiple hosts to your cluster, you can write a script to generate multiple copies of this file for each new ESXi host you’re adding.

Apply

Host customization settings are specified (manually or using a customization file) when host profile is being applied to the host. So first right click on the host and choose Host Profiles > Attach Host Profile. Then on Customize hosts page import customization file by clicking on the Browse button:

Note: If you hit the “Host settings validation failed” error after applying host customizations, read my blog article here that explains the problem.

Conclusion

Pretty simple, isn’t it? Key is to not forget that customization file can be specified either when you are applying host profile or, alternatively, you can skip host customization step and use Host Profiles > Edit Host Customizations later. For host that doesn’t have a host profile associated with it, Edit Host Customizations option will always be greyed out.

Tags: attach, cluster, csv, customisation, customization, ESXi, export, grayed out, greyed out, host profiles, import, profile, remediate, vSphere