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Read about Ansible variables and its precedence from Ansible documnet https://docs.ansible.com/ansible/latest/playbook_guide/playbooks_variables.html#variable-precedence-where-should-i-put-a-variable
We are using defaults variables, group variables, host variables and extra variables.
default variables: added in ansible roles defaults file
group variables: its added in all.yml and private repo common.yml
extra variables are passed from jenkins file, while running the ansible playbooks https://github.com/project-sunbird/sunbird-devops/blob/0fd5d9a4da250ce4ac5eafad8a2aecc823c28a0d/kubernetes/pipelines/deploy_core/Jenkinsfile#L25
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