vRA Developer: Part 6 – Working with vCAC Virtual Machine Custom Properties

Gavin Stephens 2 Comments

In part 4 and part 5, I covered a lot of ground on how to work with vcac virtual machine objects, such as getting property values and discovering relationships to other entities. This post will continue exploring vcac virtual machines and will focus on custom properties.

Custom Properties are key/value pairs of data that are associated with the virtual machine. There are many default/built-in custom properties that provide the compute cluster, storage cluster, disk, cpu, network information and much more.

It’s also possible to create your own custom properties and associate these with your virtual machine deployments. This allows great flexibility as you can apply any key/value to your deployments and use this information in your workflows. An example might be to set a site identifier that associates the virtual machine to a specific site.

VMware provides a Custom Properties Reference, which details all the built-in custom properties that are available.

All code that I have provided or talked about in this post can be downloaded as a vRO package for your consumption here.

Retrieving Custom Properties Assigned to a Virtual Machine

There are two main ways to retrieve the custom properties that have been associated with a virtual machine deployment. The first, is during the build process, where an Event Broker Subscription is used to call a vRO workflow, to perform some task. The second, is by reading the custom properties from the vcac database (via the entities) for those that are related to the virtual machine.

Here is an example of a default set of Custom Properties associated with a deployed virtual machine:

The first set are prefixed with a double underscore (__), which denotes that these are ‘hidden’ properties that are used by the system and provide object references to the reservation and the request (note that these properties will not be referenced in the official VMware Custom Properties Reference).

The remaining properties are the key/values associated with the virtual machine and can provide cpu count, amount of assigned memory, used storage, etc. and any user-defined custom properties that you have created. Unlike the hidden properties. you will find a reference to all of these in the VMware Custom Properties Reference.

One important thing to note, is that when you are working with custom property values, these are always returned as a string, regardless of what data is being stored. I.e. if a custom property has a value of ‘false’, this is the literal string “false” and not Boolean false. Read More

vRA Developer: Part 5 – Working with vCAC Virtual Machine Linked Entities

Gavin Stephens 1 Comment

In my previous post vRA Developer: Part 4 – Working with vCAC Virtual Machine Entities, I demonstrated how you could find vCAC virtual machine entities and retrieve and update their properties. In this post I am going to focus on linked entities.

All code that I have provided or talked about in this post can be downloaded as a vRO package for your consumption here.

There are additional properties that can be retrieved which are part of other entities that the virtual machine has a relationship with. Here are some examples of information that can be retrieved through linked entities (the code for all of these examples is included in the package link provided at the beginning of this post).

  • Host/Cluster Name
  • Reservation Name
  • Owner Username
  • IPv4 Addresses
  • Snapshots
  • Networks

The virtual machine entity object has a method ‘.getLink(vcacHost, “linkKey_string”)‘ that can be used to get the linked entity objects. The ‘.getProperty(“key_string”)‘ can then be used on these entities to get a specific property value, such as the reservation name.

Get the Host or Cluster Name

The following code can be used to get the host or cluster name that the virtual machine (this is referred to as the compute resource within the vRA portal) is hosted on.

Log output:

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vRA Developer: Part 4 – Working with vCAC Virtual Machine Entities

Gavin Stephens 2 Comments

In the first post in this series, vRA Developer: Part 1 – IaaS & Understanding The Entity Framework I detailed how you can view the vCAC entities and their associated properties. In this post I am going to cover how you can find a virtual machine entity using different property references and get/update their properties in your vRO workflows. I had intended to provide a single post for this, but felt it would be useful to provide a number of posts, for each specific vCAC entity type. In this post I am going to be looking at the vCAC virtual machine entities.

All code that I have provided or talked about in this post can be downloaded as a vRO package for your consumption here.

Finding vCAC Virtual Machine Entities

When I need to find a vCAC virtual machine entity, there are 4 search references that work well for all of my use cases. These are to search by:

  • VirtualMachineID – The entity ID.
  • VirtualMachineName – The VM name. Take caution as it’s possible to have duplicate entities with the same VirtualMachineName.
  • VMUniqueID – The unique identifier for the vm (i.e. vCenter VM instance UUID).
  • ExternalReferenceId – The external reference id (i.e. vCenter VM Id (MoRef)).

I have provided all the Actions below which perform these searches and an example log output for each.

Find Virtual Machine By Entity Id

The following code can be used to get the virtual machine entity by its entity id.

Log output:

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Advanced vRA Data Collection vRO Workflow

Gavin Stephens 2 Comments

Data Collection in vRealize Automation is a process that keeps the vRA database in sync with endpoints such as vCenter Server. Most people reading this most likely already know how clunky this process is. Also, It’s not immediately obvious how this process can be automated from a vRO prospective. If you are performing any tasks against objects on your endpoints, such as day 2 actions that add or remove hard disks, networks, etc (and not using the OOTB reconfigure actions) then you almost certainly need to be able to programmatically invoke the data collection process to update all the information in vRA.

I have come across many different snippets of code that solved parts of the problem but were far from perfect and the code was ugly. I therefore decided to create something to make this process easy, whilst providing some additional quality of life features. So I present my Advanced Data Collection workflow for your pleasure.

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Implementing Process Locks in vRO Workflows

Gavin Stephens Leave a comment

I discovered last week that a developer wasn’t aware that you could use a locking semaphore in vRO. They were writing some API calls and encountered a 409 (conflict) error when a workflow was attempting to concurrently update the same resource (a load balancer if I recall but can’t remember the exact details). I felt that there may be other developers out there who are also not aware so I have created two workflows that can be used to create and remove process locks in your vRO workflows.

vRO provides an always available Locking System that can be used to create a lock for a given id and owner. It does this by creating a record in the embedded PostgreSQL database. When an attempt is made to create another record in the database, a key constraint occurs and the lock fails.

You should consider using a process lock if you are updating any resources that could cause a conflict or data consistency problems. Some examples include, updating a load balancer, updating a vRA Reservation, or preventing a data collection task from running because there is already one in progress. It is also useful to create a lock between sections of code in your workflow, which could cause a problem if the workflow was executed multiple times, simultaneously. Note, that you don’t always need to lock the entire workflow, just between areas of code where updates are performed. Read More

Resolve vRA/vCAC VM to vCenter VM

Gavin Stephens 1 Comment

I wrote this post some time ago but I felt that it didn’t include some other use cases where you would want to resolve a vCenter virtual machine. I also previously used code that was provided by the vRO appliance that I wasn’t too keen on (logging was a bit light and there was code to search using the BIOS UUID, which we don’t care about). I have therefore updated this post to reflect the following use cases:

  • Find the vCenter VM by its instance Uuid when using the Event Broker;
  • Find the vCenter VM by its instance Uuid on a specific vCenter Server;
  • Find the vCenter VM by its name, on a specific vCenter Server and a specific folder;
  • Find the vCenter VM by its MoRef id on a specific vCenter Server;

Hopefully, there should be enough code provided here to help you achieve your goal no matter what your scenario. However, if you need something different, then feel free to contact me and I will try to help. Read More

vRA Developer: Part 3 – Performing CRUD Operations on IaaS Entity Objects

Gavin Stephens 3 Comments

In a previous post vRA Developer: Part 1 – IaaS & Understanding The Entity Framework I detailed what the Entity Framework is and how objects and their properties could be discovered using an application called LINQPad.

This post is going to detail how we can interact with the IaaS servers and work with the objects within the Entity Framework. I have also written a number of actions that provide a standard interface to use when working with the entities and perform CRUD (Create, Read, Update, Delete) operations on them. 

Note: these actions are designed to be used with wrappers for your code (i.e. other actions performing a task, which call these actions) and not directly in your workflows (although there is no real harm if you want to, it’s just cleaner not to). Read More

vRA Developer: Part 2 – Dynamically Discover vCAC and vCACCAFE endpoints in vRO

Gavin Stephens Leave a comment

When I work with endpoints in vRO, I like to use actions to discover these instead of hard coding them as attributes or within configuration elements. Hard coding of these endpoints requires manual configuration steps when moving code between environments, which is not ideal. I felt it would be a good idea to include this post early on within this series, as these hosts are often dependencies when working with a lot of my code.

All code that I have provided or talked about in this post can be downloaded as a vRO package for your consumption here.

Discover vRealize Automation Infrastructure (vCAC IaaS) Endpoint

You will generally only have a single vCAC IaaS endpoint in your vRO inventory. I have never worked in an environment where there was more than one. Therefore, the action I have created below requires no inputs and will attempt to discover this single vCAC IaaS endpoint. If you have more than one host for some reason then it should be fairly easy to incorporate this.

Log output:

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