7.2

You can write your own custom scripts for the guest agent to run on deployed machines, and use custom
properties on the machine blueprint to specify the location of those scripts and the order in which to run
them. You can also use custom properties on the machine blueprint to pass custom property values to
your scripts as parameters.
For example, you could use the guest agent to make the following customizations on deployed machines:
n
Change the IP address
n
Add or format drives
n
Run security scripts
n
Initialize another agent, for example Puppet or Chef
You can also provide an encrypted string as a custom property in a command line argument. This allows
you to store encrypted information that the guest agent can decrypt and understand as a valid command
line argument.
Your custom scripts do not have to be locally installed on the machine. As long as the provisioned
machine has network access to the script location, the guest agent can access and run the scripts. This
lowers maintenance costs because you can update your scripts without having to rebuild all of your
templates.
You can configure security settings for the virtual machines to be provisioned by specifying information in
a reservation, blueprint, or guest agent script. If the machines to be provisioned requires a guest agent,
you must add a security rule that contains that requirement to the reservation or the blueprint. For
example, if you use a default security policy that denies communication between all machines, and rely
on a separate security policy to allow communication between specific machines, the guest agent might
be unable to communicate with vRealize Automation during the customization phase. To avoid this
problem during machine provisioning, use a default security policy that allows communication during the
customization phase.
If you choose to install the guest agent to run custom scripts on provisioned machines, your blueprints
must include the appropriate guest agent custom properties. For example, if you install the guest agent
on a template for cloning, create a custom script that changes the provisioned machine's IP address, and
place the script in a shared location, you need to include a number of custom properties in your blueprint.
Table 1‑7. Custom Properties for Changing IP Address of a Provisioned Machine with a Guest
Agent
Custom Property Description
VirtualMachine.Admin.UseGuestAgent
Set to true to initialize the guest agent when the provisioned
machine is started.
VirtualMachine.Customize.WaitComplete
Set to True to prevent the provisioning workflow from sending
work items to the guest agent until all customizations are
complete.
Configuring vRealize Automation
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