Ansible allows you to deploy and configure using the same tool, so you would likely reuse groups and just keep the OS configuration in separate playbooks from the app deployment. A system can be in multiple groups. This does not just apply to clouds — If you have another system maintaining a canonical list of systems in your infrastructure, usage of dynamic inventory is a great idea in general. Now what sort of use cases does this layout enable? NOTE: These may not use all of the features in the latest release, but are still an excellent reference! Your environments need not be the same size and you can use group variables to control the differences between those environments.
Tags are natural way to go.
Best Practices — Ansible Documentation
Three ways of specifying them for roles below: name: apply the webserver configuration hosts: webservers roles. One crucial way to organize your playbook content is Ansible's “roles”. ansible- playbook --limit webservers ansible-playbook Create second role tests_ansible2 with the following: -- - name: "echo ansible- playbook -i inventory --limit first_host_group.
This is shown in the directory structure example at the start of this section. You can find some example playbooks illustrating these best practices in our ansible-examples repository.
Sometimes Ansible just can't cut performing a task using the built-in modules.
How to run only one role of an Ansible playbook Stack Overflow
If updating a webserver farm you really want to use it to control how many machines you are updating at once in the batch. If a playbook has a. Any variable can be set via the command line. There is a wealth of modules available, and writing your own should only be done as an absolute last resort.
Ansible playbook limit role
|See Roles for more information.
Sometimes Ansible just can't cut performing a task using the built-in modules. The above setup models a typical configuration topology. Below is an example tasks file that explains how a role works. This has changed drastically between Ansible versions pre For general maintenance, it is often easier to use grepor similar tools, to find variables in your Ansible setup.
Video: Ansible playbook limit role 017 Ansible Roles Ansible Galaxy
role: db_server > tags: db_server_role > - web_server > tags: web_server_role > > $ --tags db_server_role >. Limit to one host ansible-playbook playbooks/ --limit " host1". Limit to multiple hosts.
This allows playbooks to target machines based on role, as well as to assign role specific variables using the group variable system.
Running commands Ansible Tips and Tricks
Using raw module to run command similar to running directly via SSH : ansible -m raw -s -a "yum install libselinux-python -y" new-atmo-images Other times, Ansible's modules either aren't well defined yet, or simply do not exist. Below, the production file contains the inventory of all of your production hosts. See Working With Dynamic Inventory.
This way you have an audit trail describing when and why you changed the rules that are automating your infrastructure.
ubuntu how to execute a particular role of ansible Server Fault
Here is an example handlers file.
Ansible playbook limit role
|As also mentioned above, a good way to keep your staging or testing and production environments separate is to use a separate inventory file for staging and production.
This does not just apply to clouds — If you have another system maintaining a canonical list of systems in your infrastructure, usage of dynamic inventory is a great idea in general. Learn how to extend Ansible by writing your own modules Working with Patterns Learn about how to select hosts GitHub examples directory Complete playbook files from the github project source Mailing List Questions?
Use version control. This best practice has no limit on the amount of variable and vault files or their names. If you are using a cloud provider, you should not be managing your inventory in a static file.
Ansible tags are a powerful way to limit the amount of work that gets done.
Running ansible-playbook without any --tags produces all the debug or role, so that these tasks can be selectively run when the playbook is. When writing Ansible roles I occasionally want a way to just run a role from the command line, without having to muck about with a playbook.
See Working with Inventory and Working with Patterns.
More information for shell and command modules. Again, if we are using dynamic inventory sources, many dynamic groups are automatically created. Follow this link to see how this can be done.
This is shown in the directory structure example at the start of this section. Learn how to extend Ansible by writing your own modules Working with Patterns Learn about how to select hosts GitHub examples directory Complete playbook files from the github project source Mailing List Questions?
See Roles for more information.