Once your inventory is defined, you use patterns to select the hosts or groups you want Ansible to run against. Introduced in version 2. The inventory file can be in one of many formats, depending on the inventory plugins you have.
The headings in brackets are group names, which are used in classifying hosts and deciding what hosts you are controlling at what times and for what purpose. There are two default groups: all and ungrouped. The all group contains every host. Every host will always belong to at least 2 groups all and ungrouped or all and some other group.
You can and probably will put each host in more than one group. For example a production webserver in a datacenter in Atlanta might be included in groups called [prod] and [atlanta] and [webservers]. You can create groups that track:. You can see that one. You can also use nested groups to simplify prod and test in this inventory, for the same result:.
You can find more examples on how to organize your inventories and group your hosts in Inventory setup examples. If you have a lot of hosts with a similar pattern, you can add them as a range rather than listing each hostname separately:. For numeric patterns, leading zeros can be included or removed, as desired. Ranges are inclusive. You can also define alphabetic ranges:. You can store variable values that relate to a specific host or group in inventory.
To start with, you may add variables directly to the hosts and groups in your main inventory file. As you add more and more managed nodes to your Ansible inventory, however, you will likely want to store variables in separate host and group variable files. Unique values like non-standard SSH ports work well as host variables. You can add them to your Ansible inventory by adding the port number after the hostname with a colon:.
If you list non-standard SSH ports in your SSH config file, the openssh connection will find and use them, but the paramiko connection will not. This only works for hosts with static IPs, or when you are connecting through tunnels. Generally speaking, this is not the best way to define variables that describe your system policy.
Setting variables in the main inventory file is only a shorthand. If all hosts in a group share a variable value, you can apply that variable to an entire group at once. In INI:. Group variables are a convenient way to apply variables to multiple hosts at once. Before executing, however, Ansible always flattens variables, including inventory variables, to the host level. If a host is a member of multiple groups, Ansible reads variable values from all of those groups.
If you assign different values to the same variable in different groups, Ansible chooses which value to use based on internal rules for merging. You can apply variables to these groups of groups using :vars or vars: :.Ansible delivers simple IT automation that ends repetitive tasks and frees up DevOps teams for more strategic work.
Leverage powerful automation across entire IT teams no matter where you are in your automation journey. March 1, by Bill Nottingham.
These new features allow you to use Ansible Tower automation more flexibly in ways that match both the structure of your organization and your infrastructure. Ansible introduced Clusters in Ansible Tower 3. Tower Clusters allow you to add capacity to your Ansible Tower environment - the more nodes in your Tower Cluster, the more job execution capacity you have. If you have to run many jobs simultaneously, adding more nodes to the cluster lets you run them all without queueing.
However, this just gives you an additional mass of capacity. If you just have one group using a Tower instance, that may be enough. But we know that many Ansible Tower instances are shared among teams, groups, and organizations that may have different uses for their automation.
An Ansible Tower Instance group is a set of cluster nodes dedicated for a particular purpose. You can organize your Ansible Tower Cluster into any number of instance groups, and cluster nodes can exist in multiple instance groups. Each instance group has its own job queue, and any node in the group can take jobs off of that queue.
Jobs can be assigned to an instance group in three ways - by the organization, by the inventory, or by the individual job template. You can create as many instance groups as you need, and put nodes in as many different groups as needed, as long as at least one node exists in the base [tower] group.
Note that all job events from running jobs are processed by the [tower] group, so the number of nodes in the [tower] group does need to scale with your job load even if it is not being used for direct job execution. To configure an organization, inventory, or job template to use a particular instance group, just configure it under the respective organization, inventory, or job template.
In this case, you can set up three instance groups for each team to use in their environments. These instance groups can share some nodes with the main [tower] group, so you can have shared global capacity, while each having some dedicated capacity. The following inventory setup sets up an emergency patching server. Many people use Ansible to manage far-flung, complex infrastructures. They can have machines and networks in multiple datacenters, servers behind firewalls or in VPCs, or remote devices where unstable links may not survive the length of the job.
In all these cases, it can be simpler to run automation local to the nodes. An Isolated Node is an Ansible Tower node that contains a small piece of software for running playbooks locally to manage a set of infrastructure. When a job is run that targets things managed by the isolated node, the job and its environment will be pushed to the isolated node over SSH, where it will run as normal.
Periodically, the master Ansible Tower cluster will poll the isolated node for status on the job, updating in as close to real-time as possible. When it finishes, the remote execution on the isolated node will be cleaned up, and the job status will be updated in Ansible Tower. Isolated nodes are also set up in the inventory file used by the Ansible Tower setup program. Isolated nodes make up their own instance group.Tower can be installed in various ways by choosing the best mode for your environment and making any necessary modifications to the inventory file.
Tower will not configure replication or failover for the database that it uses, although Tower should work with any replication that you have. The database server should be on the same network or in the same datacenter as the Tower server for performance reasons. Tower can be installed in a high availability cluster mode. In this mode, multiple Tower nodes are installed and active. Any node can receive HTTP requests and all nodes can execute jobs.
Running in a cluster setup requires any database that Tower uses to be external—PostgreSQL must be installed on a machine that is not one of the primary or secondary tower nodes.
The contents of the inventory file should be defined in.
Ansible – Classroom Notes 12/April/2020
For installations and upgrades : If you need to make use of external databases, you must ensure the database sections of your inventory file are properly setup. Edit this file and add your external database information before running the setup script. For upgrading an existing cluster : When upgrading a cluster, you may decide that you want to also reconfigure your cluster to omit existing instances or instance groups.
Omitting the instance or the instance group from the inventory file will not be enough to remove them from the cluster.
In addition to omitting instances or instance groups from the inventory file, you must also deprovision instances or instance groups before starting the upgrade. Otherwise, omitted instances or instance groups will continue to communicate with the cluster, which can cause issues with tower services during the upgrade. For clustered installations : If you are creating a clustered setup, you must replace localhost with the hostname or IP address of all instances.
For all standard installations : When performing an installation, you must supply any necessary passwords in the inventory file. Changes made to the installation process now require that you fill out all of the password fields in the inventory file. If you need to know where to find the values for these they should be:.
Once any necessary changes have been made, you are ready to run. Root access to the remote machines is required. With Ansible, this can be achieved in different ways:. For more information on become plugins, refer to Understanding Privilege Escalation and the list of become plugins. Ansible Tower 3.
Users of older versions should follow the instructions available in the v. The Tower setup playbook script uses the inventory file and is invoked as. Please note that a issue was discovered in Tower 3.
If you need to back up or restore your Tower v3. After calling. Once setup is complete, use your web browser to access the Tower server and view the Tower login screen. Once installed, if you log into the Tower instance via SSH, the default admin password is provided in the prompt.
You can then change it with the following command as root or as AWX user :. Are you using the latest and greatest version of Ansible Tower? Find the Ansible Tower documentation set which best matches your version of Tower. Ansible Tower Installation and Reference Guide v3.Ansible delivers simple IT automation that ends repetitive tasks and frees up DevOps teams for more strategic work.
Leverage powerful automation across entire IT teams no matter where you are in your automation journey. May 26, by Jake Jackson. Welcome to another post in our Getting Started series. In our previous post, we discussed how you can equip your Ansible Tower instance with users and credentials. In this post, we will discuss how to set up projects and inventories in your Ansible Tower instance. Tower projects are a logical collection of Ansible Playbooks that are set up with each other based on what they might be doing or which hosts they might interact with.
Managing your projects with an SCM is recommended to ensure that only users with assigned access to the repository can change the playbook before execution, and for the extra layer of accountability and change control, it provides. Selecting "clean" clears out old managed files and unmanaged files in the directory for that project. Upon arriving to the new project page, name the project and select what organization within your instance will be using this project.
Select the source for this project, whether that be locally or through an SCM. Once you have declared the source, you can select "clean", "delete on update" and "update on launch" from the SCM update options.
Once you have the correct source and you have selected the options you need, hit the save button and you will be returned to the Projects page with your new project listed. Now that you have set up a Tower project, all you need is some hosts nodes to automate and you will be cooking with gas. Within Tower, the hosts that you interact with are set up as collections within Tower called inventories. Tower divides inventories into groups and the groups are what contain the actual hosts.
This ensures your inventory is always up to date. For more on what is included with dynamic inventories in Tower, check out these docs.
For the purpose of this blog post, I will go through the steps to add a static inventory to demonstrate the process. To start, from the Tower dashboard, select the inventories header. This will take you to the inventories page where all of your current inventories will be displayed. Once that is done, select save.
Note: You are not done, your inventory still needs hosts!Ansible delivers simple IT automation that ends repetitive tasks and frees up DevOps teams for more strategic work. Leverage powerful automation across entire IT teams no matter where you are in your automation journey. September 22, by Chris Meyers. The feature allows you to generate a new Inventory that is made of up hosts existing in other Inventory in Ansible Tower.
This inventory is always-up-to-date and is populated using what we call a host filter. Effectively, this allows you create an Inventory of Hosts and their relational fields as well as related JSON structures. Ansible Tower bolts on an Ansible fact cache plugin with Job Template that have fact caching enabled. In this blog post I will show you how to overcome this limitation and add hosts to a Smart Inventory using, for example, a range query on if a host is part of a subnet.
We are going to have to create objects in Ansible Tower. Specifically, the objects in the table below. Run the gather job template. Then look at the resulting facts that got gathered in the UI for the Inventory Autobots. Above is an example of how you view the results from the fact gathering process in the UI. We will create a smart inventory that contains only Red Hat hosts. In my example, optimus and bumblebee are both Red Hat hosts while jazz is an Ubuntu host.
We are now going to leave the Smart Inventory feature and go back to fact caching. Below is the result of that run. Notice how bumblebee now has a new set of facts see below image. The pieces are:. This is a good example because selecting hosts based on subnet is a range query, it is not a simple equality query. Therefore, we are going to need to leverage 3. Inject playbook facts to accomplish creating a Smart Inventory to group these hosts. The below playbook accomplishes this. Currently, all traditional relational database fields on Ansible Tower objects can be used in a Smart Inventory host filter query i.
We hope to expand the searchable JSON fields in the future as well as the operators supported right now we only support equality. However, much consideration must be given to the performance characteristics as well as the storage requirements in doing so. Topics: Ansible Tower. RSS Feed. Toggle navigation. Overview Why Ansible?
Overview Pricing.An Inventory is a collection of hosts against which jobs may be launched, the same as an Ansible inventory file. Inventories are divided into groups and these groups contain the actual hosts. If you have a custom dynamic inventory script, or a cloud provider that is not yet supported natively in Tower, you can also import that into Tower. This tab displays a list of the inventories that are currently available.
The inventory list may be sorted and searched by NameTypeor Organization. Type : Identifies whether it is a standard inventory or a Smart Inventory. Actions : The following actions are available for the selected inventory:. If deleting items that are used by other work items, a message opens listing the items are affected by the deletion and prompts you to confirm the deletion.
Some screens will contain items that are invalid or previously deleted, so they will fail to run.Working with Ansible Dynamic Inventory
Below is an example of such a message:. A Smart Inventory is a collection of hosts defined by a stored search that can be viewed like a standard inventory and made to be easily used with job runs. Organization administrators have admin permission to inventories in their organization and can create Smart Inventories.
You can define a Smart Inventory using the same method being used with Tower Search. InventorySource is directly associated with an Inventory. The Inventory model has the following new fields that are blank by default but are set accordingly for Smart Inventories:. The membership table is updated every time a job runs against a smart inventory. This will update memberships in the following events:.
However, this will not give them any special permissions to hosts which live in a different inventory. Hosts associated with the Smart Inventory are manifested at view time. If the results of a Smart Inventory contains more than one host with identical hostnames, only one of the matching hosts will be included as part of the Smart Inventory, ordered by Host ID. Starting in 3. The plugins that are enabled in Ansible 2. If you already have an inventory source set up, then Tower automatically switches to use the inventory plugins depending on the source and Ansible version, but continue to maintain the same content previously in those scripts.
If you need to control the version of Ansible being used, you can use custom virtual environments for the inventory source. Refer to Using virtualenv with Ansible Tower. Adding a new inventory involves several components. Click below to jump to a specific component:. The type of inventory is identified by the labels and the row of tabs across the top of the create form.
Description : Enter an arbitrary description as appropriate optional. These options are based on the organization you chose. Filters are similar to tags in that tags are used to filter certain hosts that contain those names.
Therefore, to populate the Smart Host Filter field, you are specifying a tag that contains the hosts you want, not actually selecting the hosts themselves. Enter the tag in the Search field and press [Enter].Ansible delivers simple IT automation that ends repetitive tasks and frees up DevOps teams for more strategic work.
Leverage powerful automation across entire IT teams no matter where you are in your automation journey. March 18, by Sean Cavanaugh. This blog covers three quick and effective ways to connect your existing Ansible inventory into Ansible Tower:. Dynamic inventory retrieves your inventory from an existing source. The command line tool awx-managewhich comes with your Ansible Tower installation, is a simple and effective tool to import your inventory.
The awx-manage command line tool is very simple and fast.
It only took me a couple seconds to take my existing inventory and import it into Ansible Tower. For teams that use Ansible Tower to run playbooks, but manage inventory outside of Ansible Tower, importing with awx-manage is not the best option, since you would need to re-import the flat-file inventory every time a change is made to your inventory file.
If your team will continue to manage inventory outside of Ansible Tower, you probably want to use the GitHub option described below. You can use the Ansible Tower modules to automate the transfer of your inventory into Ansible Tower. These modules make it possible to use Ansible Playbooks to automate and manage everything, including inventory, in your Ansible Tower instance. The Ansible Playbook will look like this:.
The Ansible Playbook will add all devices in the group routers simultaneously. The playbook output will look similar to this:. The final method I want to cover in this post is using source control to manage my inventory. I have a flat-file inventory file stored in a Github repo.
Unlike the previous two methods, this is not meant as a migration strategy, but a more permanent way to manage your Ansible inventory using git and source control.
Inventory can be managed in Github and Ansible Tower can simply reflect those changes. First we need to create an Ansible Tower Project. Using source control for managing inventory is popular with Ansible Tower users and can scale really well. If you want to learn more Red Hat Ansible Tower concepts and gets some hands-on keyboard time please check out our free Ansible Workshops. RSS Feed.
Toggle navigation. Overview Why Ansible? Overview Pricing. Consulting for Ansible Adopt and integrate Ansible to create and standardize centralized automation practices.
Get Started Ansible is powerful IT automation that you can learn quickly. Quick Start Video. Ansible Blog Ansible Docs Partners. Join the Community Ansible is open source and created by contributions from an active open source community. Ansible Meetups Find out what's happening in global Ansible Meetups and find one near you. Ansible Galaxy The Ansible community hub for sharing automation with everyone.