Quick Bytes IT Stuff

Ansible playbook to illustrate how "when" conditional statement works in Ansible. Ansible playbook below will run a command: "file -s /dev/sdb"  The output of the command will be saved to the variable: save_the_command_output  Yes, the name of the variable can be anything. Just changed it to something that is sensible. save_the_command_output is just a string to illustrate its functionality or usage. After registering or saving the output to a variable, another command will be executed provided the conditional statement "when" is True or the condition is meet or satified. If the conditional statement is not meet then the command will be bypass or will not be executed. On this illustration below, if the conditional statement has been meet. Then a file with a filename "condition_ok" will be written on /tmp directory. Otherwise, if the condition is not meet then no file will be created. Sample playbook below: #=================== --- -  hosts: local...

Backing up every configuration before any change is a good idea.  With the Git tool, every revision or change can be keep track and changes can be reversed. However, not everything is in Git. For example, in Linux configuration on /etc configuration or other important location or files is not under Git. To keep track of the changes, old school method can still be applied. Making another copy of the file, or just simply commenting every line and adding changes or new configuration after commenting the existing lines or configuration; are forms of backup. Existing configuration can still be seen, and can put back if there's a need to reverse the configuration. In an environment where there is hundred or more virtualized machines, Ansible is a way to go.  Ansible can do the task to comment all the existing lines and apply new configurations. Ansible script below, are references from multiple sources found on the web to create this Ansible script below. Here's the Ansible, save it...

How to uncomment or enable a setting in a config file in Linux using Ansible? Ansible is quite a good tool,  as it helps to make a lot of changes on a few servers with a minimal effort. Of course, the challenge is you need to know what you want. And also create an Ansible yaml file that will accomplish the task. Example YAML file for Ansible below is able to make some changes on the Linux logrotate.conf file. On Linux logrotate.conf, it has some text like the string below. Note this is just an example and you can tweak it to other settings as desired. # uncomment this if you want your log files compressed #compress The logrotate.conf file, the compress setting is commented. To enable the setting the # or the comment key must be removed. How to remove the comment in order to enable the setting? Well, if there's only a single server do it the simple way. Login to the server and edit the file using vim or nano or other text editor. However, if there are quite a few servers. Ansible ...