ansible_default_ipv4 is not what you think

Most people think that ansible_default_ipv4 is some magical way to guess what IP address is the ‘main’ IP for a server.

It is not.

recovering Ceph from “Reduced data availability: 3 pgs inactive, 3 pgs incomplete”

When your pool stuck and you don’t know what to do.

import_playbook with play-level condition

There is a very strange feature in Ansible. As far as I can see, it’s non-documented, but I found it extremely useful. (Scroll down to the…

Data manipulation in Ansible: json_query

The second big change in Ansible is an introduction of json_query filter in templates. It is big, because it allows to perform complicated queries without invoking slow Ansible loops. Whole data processing happens almost instantly, without cluttering output.

Using block for handlers in Ansible

Sometimes you want to run few operations for your handler instead of just one. In my case, a handler was designed to restart a main service, but with few conditions:

• This service may create a ‘lock file’ which says ‘do not restart me now’…

‘is defined’ in Ansible

There is a very special construction in Jinja2/Ansible: ‘foo is defined’, which allows you to check if foo is existing at all. It’s usually used in this form:

...
when: foo is defined and foo == True

2.5: delegate_to, include_role with loops

There is a horrible regression in Ansible 2.5.

In Ansible version 2.4, if you have combination of delegate_to and include_role a given role was delegated to specified host. In Ansible 2.5 delegated role will be executed on the…

Data manipulation in Ansible: string transformation

It’s horrible. Kids, never do this!

I have a list (let’s say ‘data’), which contains stings. I need to add prefix and suffix to each string without involving Ansible loops (for example…

Using dynamic groups in ansible

When we have a condition which need to be checked for many tasks, it may be advisable to just exclude hosts (based on this condition) from been run at all.

I played with idea of dynamic groups, and here are my observations.