Red Hat Ansible Automation Platform planning guide

The Red Hat Ansible Automation Platform 2.4 reference architecture provides an example setup of a standard deployment of Ansible Automation Platform using automation mesh on Red Hat Enterprise Linux. The deployment shown takes advantage of the following components to provide a simple, secure and flexible method of handling your automation workloads, a central location for content collections, and automated resolution of IT requests.

The architecture for this example consists of the following:

Figure 2.1. Example Ansible Automation Platform 2.4 architecture

Ansible automation hub is a repository for certified content of Ansible Content Collections. It is the centralized repository for Red Hat and its partners to publish content, and for customers to discover certified, supported Ansible Content Collections. Red Hat Ansible Certified Content provides users with content that has been tested and is supported by Red Hat.

Private automation hub provides both disconnected and on-premise solutions for synchronizing content. You can synchronize collections and execution environment images from Red Hat cloud automation hub, storing and serving your own custom automation collections and execution images. You can also use other sources such as Ansible Galaxy or other container registries to provide content to your private automation hub. Private automation hub can integrate into your enterprise directory and your CI/CD pipelines.

A high availability (HA) configuration increases reliability and scalablility for automation hub deployments.

HA deployments of automation hub have multiple nodes that concurrently run the same service with a load balancer distributing workload (an "active-active" configuration). This configuration eliminates single points of failure to minimize service downtime and allows you to easily add or remove nodes to meet workload demands.

The Event-Driven Ansible controller is the interface for event-driven automation and introduces automated resolution of IT requests. Event-Driven Ansible controller helps you connect to sources of events and act on those events by using rulebooks. This technology improves IT speed and agility, and enables consistency and resilience. With Event-Driven Ansible, you can:

Automation mesh is an overlay network intended to ease the distribution of work across a large and dispersed collection of workers through nodes that establish peer-to-peer connections with each other using existing networks.

Automation mesh provides:

Automation execution environments are container images on which all automation in Red Hat Ansible Automation Platform is run. They provide a solution that includes the Ansible execution engine and hundreds of modules that help users automate all aspects of IT environments and processes. Automation execution environments automate commonly used operating systems, infrastructure platforms, network devices, and clouds.

Ansible Galaxy is a hub for finding, reusing, and sharing Ansible content. Community-provided Galaxy content, in the form of prepackaged roles, can help start automation projects. Roles for provisioning infrastructure, deploying applications, and completing other tasks can be dropped into Ansible Playbooks and be applied immediately to customer environments.

Automation content navigator is a textual user interface (TUI) that becomes the primary command line interface into the automation platform, covering use cases from content building, running automation locally in an execution environment, running automation in Ansible Automation Platform, and providing the foundation for future integrated development environments (IDEs).

Your system must meet the following minimum system requirements to install and run Red Hat Ansible Automation Platform.

The following are necessary for you to work with project updates and collections:

Automation controller is a distributed system, where different software components can be co-located or deployed across multiple compute nodes. In the installer, four node types are provided as abstractions to help you design the topology appropriate for your use case: control, hybrid, execution, and hop nodes.

Use the following recommendations for node sizing:

Execution nodes

Execution nodes run automation. Increase memory and CPU to increase capacity for running more forks.

Control nodes

Control nodes process events and run cluster jobs including project updates and cleanup jobs. Increasing CPU and memory can help with job event processing.

Hop nodes

Hop nodes serve to route traffic from one part of the automation mesh to another (for example, a hop node could be a bastion host into another network). RAM can affect throughput, CPU activity is low. Network bandwidth and latency are generally a more important factor than either RAM or CPU.

Automation hub enables you to discover and use new certified automation content from Red Hat Ansible and Certified Partners. On Ansible automation hub, you can discover and manage Ansible Collections, which are supported automation content developed by Red Hat and its partners for use cases such as cloud automation, network automation, and security automation.

Automation hub has the following system requirements:

The Event-Driven Ansible controller is a single-node system capable of handling a variable number of long-running processes (such as rulebook activations) on-demand, depending on the number of CPU cores. Use the following minimum requirements to run, by default, a maximum of 12 simultaneous activations:

Red Hat Ansible Automation Platform uses PostgreSQL 13. PostgreSQL user passwords are hashed with SCRAM-SHA-256 secure hashing algorithm before storing in the database.

To determine if your automation controller instance has access to the database, you can do so with the command, awx-manage check_db command.

Choose the Red Hat Ansible Automation Platform installer if your Red Hat Enterprise Linux environment is connected to the internet. Installing with internet access retrieves the latest required repositories, packages, and dependencies. Choose one of the following ways to set up your Ansible Automation Platform installer.

When you use the RPM installer, the files are placed under the /opt/ansible-automation-platform/installer directory.

Use the Red Hat Ansible Automation Platform Bundle installer if you are unable to access the internet, or would prefer not to install separate components and dependencies from online repositories. Access to Red Hat Enterprise Linux repositories is still needed. All other dependencies are included in the tar archive.

You can deprovision nodes and instance groups using the Ansible Automation Platform installer. Running the installer will remove all configuration files and logs attached to the nodes in the group.

To deprovision nodes, append node_state=deprovision to the node or group within the inventory file.

For example:

To remove a single node from a deployment:

[automationcontroller]
host1.example.com
host2.example.com
host4.example.com   node_state=deprovision

or

To remove an entire instance group from a deployment:

[instance_group_restrictedzone]
host4.example.com
host5.example.com

[instance_group_restrictedzone:vars]
node_state=deprovision

The second part of the example inventory file, following [all:vars], is a list of variables used by the installer. Using all means the variables apply to all hosts.

To apply variables to a particular host, use [hostname:vars]. For example, [automationhub:vars].

The values of string variables are declared in quotes. For example:

pg_database='awx'
pg_username='awx'
pg_password='<password>'

When declared in a :vars section, INI values are interpreted as strings. For example, var=FALSE creates a string equal to FALSE. Unlike host lines, :vars sections accept only a single entry per line, so everything after the = must be the value for the entry. Host lines accept multiple key=value parameters per line. Therefore they need a way to indicate that a space is part of a value rather than a separator. Values that contain whitespace can be quoted (single or double). For more information, see Python shlex parsing rules.

If a variable value set in an INI inventory must be a certain type (for example, a string or a boolean value), always specify the type with a filter in your task. Do not rely on types set in INI inventories when consuming variables.

If a parameter value in the Ansible inventory file contains special characters, such as #, { or }, you must double-escape the value (that is enclose the value in both single and double quotation marks).

For example, to use mypasswordwith#hashsigns as a value for the variable pg_password, declare it as pg_password='"mypasswordwith#hashsigns"' in the Ansible host inventory file.

You can encrypt sensitive or secret variables with Ansible Vault. However, encrypting the variable names and the variable values makes it hard to find the source of the values. To circumvent this, you can encrypt the variables individually by using ansible-vault encrypt_string, or encrypt a file containing the variables.

You can further configure your Red Hat Ansible Automation Platform installation by including additional variables in the inventory file. These configurations add optional features for managing your Red Hat Ansible Automation Platform. Add these variables by editing the inventory file using a text editor.

A table of predefined values for inventory file variables can be found in Inventory file variables in the Red Hat Ansible Automation Platform Installation Guide.

This scenario includes installation of automation controller, including the web front end, REST API backend, and database on a single machine. It installs PostgreSQL, and configures the automation controller to use that as its database. This is considered the standard automation controller installation scenario.

This scenario includes installation of the automation controller server on a single machine and configures communication with a remote PostgreSQL instance as its database. This remote PostgreSQL can be a server you manage, or can be provided by a cloud service such as Amazon RDS.

This scenario includes installation of Event-Driven Ansible controller on a single machine with an internal database. It installs an installer managed PostgreSQL that is similar to the automation controller installation scenario.

This scenario includes installation of automation hub, including the web frontend, REST API backend, and database on a single machine. It installs PostgreSQL, and configures the automation hub to use that as its database.

This scenario includes installation of the automation hub server on a single machine, and installs a remote PostgreSQL database, managed by the Red Hat Ansible Automation Platform installer.

This scenario includes installation of automation controller and automation hub with a database on the automation controller node, or a non-installer managed database.

This scenario includes installation of automation controller and automation hub and configures communication with a remote PostgreSQL instance as its database. This remote PostgreSQL can be a server you manage, or can be provided by a cloud service such as Amazon RDS.

This scenario includes installation of multiple automation controller nodes and an automation hub instance and configures communication with a remote PostgreSQL instance as its database. This remote PostgreSQL can be a server you manage, or can be provided by a cloud service such as Amazon RDS. In this scenario, all automation controller are active and can execute jobs, and any node can receive HTTP requests.