Answers and/or workarounds to questions encountered when using Ansible.
Ansible is a great tool which allows for effective bootstrap and lifecycle automation.
The purpose of this repo is to help quickly find answers or more likely workarounds (if not hacks) in case of bumping into the same or similar questions.
These code snippets are not solutions and although it may help to solve some problem, it may also bring in some other issues. Use at your own risk.
What if we want to find out the value of the variable on one particular host and set this value on other hosts?
First, gather the value of the variable (e.g. erlang cookie) from desired host:
- name: Gather erlang cookie from first EMQ node
command: cat /var/lib/emqx/.erlang.cookie
when: emq_node_id | int == 1
register: emq_erlang_cookie
The fetched value is unknown to other hosts. To change this, set fact on all hosts:
- name: Set erlang_cookie fact
set_fact:
erlang_cookie: "{{ hostvars[emq_first_node]['emq_erlang_cookie']['stdout'] }}"
Finally, set the value of the variable on all other hosts:
- name: Set erlang cookie
lineinfile:
path: /var/lib/emqx/.erlang.cookie
line: "{{ erlang_cookie }}"
regexp: '\A.*'
when: emq_node_id | int > 1
register: erlang_cookie_changed
Thank you for reading so far. Did/do you happen to:
- find any error or typo?
- have a more elegant answer, workaround or better solution?
- have any other Ansible questions?
If so, you are welcome to open pull request.