TOPIC: ANSIBLE
Using inventory files with Ansible
28th October 2022This is the second post on Ansible following my main system's upgrade to Linux Mint 21. Then, I manually ran some Ansible playbooks, only to spot messages that I had not noticed before. Here, I discuss two messages issued because of an issue with an inventory file, which is where one defines lists of servers against which playbooks are executed. The default is called hosts and is located at /etc/ansible, but the system upgrade had renamed the existing one, which meant that Ansible could not find it. The solution was to take a copy and put somewhere safer. Then, I needed to add the location of the new file to the affected ansible-playbook commands using the following construct:
ansible-playbook [playbook path] -i [inventory file path]
Before I did this, I was seeing messages including the text "Could not match supplied host pattern" or others with the following text:
[WARNING]: No inventory was parsed, only implicit localhost is available
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match 'all'
The cause was the same in each case, and attending to the inventory file got rid of the unwanted messages. The new file also should not be affected by system upgrades in the future.
Fixing an Ansible warning about boolean type conversion
27th October 2022My primary use for Ansible is doing system updates using the inbuilt apt module. Recently, I updated my main system to Linux Mint 21 and a few things like Ansible stopped working. Removing instances that I had added with pip3 sorted the problem, but I then ran playbooks manually, only for various warning messages to appear that I had not noticed before. What follows below is one of these.
[WARNING]: The value True (type bool) in a string field was converted to u'True' (type string). If this does not look like what you expect, quote the entire value to ensure it does not change.
The message is not so clear in some ways, not least because it had me looking for a boolean value of True when it should have been yes. A search on the web revealed something about the apt module that surprised me.: the value of the upgrade parameter is a string, when others like it take boolean values of yes or no. Thus, I had passed a bareword of yes when it should have been declared in quotes as "yes". To my mind, this is an inconsistency, but I have changed things anyway to get rid of the message.
Changing the Ansible Vault editor from Vi to Nano
15th August 2022Recently, I got to experiment with Ansible after reading about the orchestration tool in a copy of Admin magazine. It came in handy for updating a few web servers that I have, as well as updating my main Linux workstation. For the former, automated entry of SSH passwords sufficed, but the same did not apply for sudo usage on my local machine. This meant that I needed to use Ansible Vault to store the administrator password, and doing so opened up a file in the Vi editor. Since I am not familiar with Vi and wanted to get things sorted quickly, I fancied using something more user-friendly like Nano.
Doing this meant adding the following line to .bashrc:
export EDITOR=nano
Saving and closing the file followed by reloading the session set me up for what was needed.